file which includes the original illustrations4 ,see #chjcf-;h4htm or #chjcf-;h4zip3 7https3_/_/www4gutenberg4org_/cache_/epu b_/#chjcf_/pg#chjcf-;images4html7 or 7https3_/_/www4gutenberg4org_/files_/#ch jcf_/chjcf-;h4zip7 ,idaho ,agricultural ,extension ,service ,bulletin #cif ,june1 #aifb ,t-#a ,,electricity ,,for ,,the #d-;,h ,,scientist ,safety ,uses ,economy ,division ,i #d-;,h ,electric ,university ,of ,idaho ,college of ,agriculture ,,how ,,to ,,use ,,this ,,book ,,in ,,fulfilling ,,the ,,goals ,,of ,,the #d-;,h ,,electric ,,project ,,for ,,the ,,first ,,and ,,succeeding ,,years ,the minimum goals for credit in the #d-;,h ,electric project vary according to the #d-;,h member's age and the number of years he or she has taken the electric project4 ,for example1 if you are a #d-;,h member beginning the #d-;,h ,electric project at the age of #aj1 you will not be required to earn as many credit points as a #ad-year-old #d-;,h member beginning the #d-;,h ,electric project4 ,however1 if you are a #ab-year-old in your second year of electricity you must earn as many credit points in that year as a #ad-year-old does in his or her first year4 ,each lesson or goal has been designated a certain number of credit points4 ,these are shown near the title of each lesson or goal4 ,you decide on the lessons you want to study1 list them1 and add up the credit points4 ,for a full year's #d-;,h project credit1 the total of your credit points should be at least as many as shown in the following table3 ,examples of reading the table below are as follows3 7a7 ,an #aa-year-old member is required to complete #ac credit points the first year1 7b7 ,a #ad-year-old is required to complete #ag credit points his first year1 7c7 ,a #ad-year-old taking the electric project for the third year must complete #af credit points that year4 ,we recommend that1 if you are taking the #d-;,h ,electric project1 you start with the first lesson in the book and go on through to the back of the book in advanced years4 ,but you may skip the less important or less interesting parts so long as you learn the basic lessons4 ,a way to find out whether you know the basic lessons is to read them through and try to answer all questions under the heading ,what ,did ,you ,learn4 ,if you can answer these questions you may not wish to spend the time doing the things listed under ,what ,to ,do4 ,minimum ,number of ,credit ,points ,required for ,each ,year's ,work in the #d-;,h ,electric ,project #d-;,h ,member's #d-;,h ,member's ,year in #d-;,h ,electric ,project ,age #ast ,year #bnd ,year #crd ,year #dth or ,later ,years #aj-aa #ac #ae #ab-ac #ae #ag #ai #bj #ad-ae #ag #ai #ba #ba #af over #ai #ba #ba #ba ,this system of credit points makes it possible for you to do the things you want to do with electricity and get credit for them in the #d-;,h ,electric project4 #d-;,h ,electric1 ,division ,i ,,table ,,of ,,contents ,lesson ,credit ,page ,number ,title ,points ,number ,how to ,use ,this ,book #a ,b-#a ,getting ,acquainted ,with ,electricity #c #b ,b-#b ,tools for ,electricians #d #g ,b-#c ,rewire a ,lamp--,be a ,lamp ,detective #c #aa ,b-#d ,make a ,trouble ,light #c #ae ,b-#e ,what ,makes ,motors ,run #e #ah ,b-#f ,taking ,care of ,electric ,motors #c #bc ,b-#g ,reading the ,electric ,meter #d #bf ,b-#h ,ironing is ,fun #c #cj ,b-#i ,let's ,be ,friends ,with ,electricity #b #ce ,b-#aj ,how ,electric ,bells ,work--,for ,you #c #ci ,b-#aa ,first ,aid for ,electrical ,injuries #b #dc ,b-#ab ,how ,electricity ,heats #c #dg ,b-#ac ,mysterious ,magnetism #b #ej ,b-#ad ,give ,your ,appliances and ,lights a ,square ,meal #b #ed ,b-#ae ,you ,can ,measure ,electricity #d #eh ,,university ,,of ,,idaho ,,college ,,of ,,agriculture ,,agricultural ,,extension ,,service ,eric ,b4 ,wilson1 ,extension ,agricultural ,engineer #aifb ,published and distributed in furtherance of the ,acts of ,may #h and ,june #cj1 #aiad1 by the ,university of ,idaho ,extension ,service1 ,james ,e4 ,kraus1 ,director2 and the ,u4 ,s4 ,department of ,agriculture1 ,co-operating4 ,,lesson ,,no4 ,b-l ,credit ,points #c ,,getting ,,acquainted ,,with ,,electricity ,electricity serves you best when you understand how it works and use it properly4 ,as a #d-;,h member1 you should know about electricity and help to show others the way to obtain its tremendous work-saving benefits as well as how to use it with safety4 ,a good way to think of electricity is to compare it with water4 ,it acts a lot like water4 ,however it is made of tiny parts of atoms called electrons4 ,when there are more than the normal number of electrons in anything1 it is said to be negatively charged2 when there is a shortage of electrons1 it is positively charged4 ,as water flows downhill1 seeking it's level1 electrons flow from negative to positive1 seeking to balance the charge4 ,electrical ,conductors ,even if you're never going to repair a lamp or make a chick brooder1 you should know about conductors and insulators4 ,this is because you happen to be a fairly good conductor of electricity4 ,electricity will pass easily through you to other conductors--the ground1 for instance4 ,when this happens you may get a shock1 burn1 or serious injury4 ,but it doesn't ever have to happen1 if you learn to understand your friend1 electricity4 ,silver1 copper1 iron1 aluminum and many other metals are very good conductors4 ,water1 acids1 and salts are too4 ,electricity passes over or through them very easily4 ,like water pipes1 the larger the conductor1 the more electricity it can carry4 ,when conductors are too small for the amount of electrons trying to move over them1 they get hot1 melt1 may start fires4 ,that's why wire size is important4 ,electrical ,insulators ,insulators are the opposite of conductors4 ,electricity has trouble passing through some materials4 ,rubber1 most plastics1 dry wood1 oils and glass are some of the good insulators4 ,it's the amount and kind of insulation that counts4 ,if it has enough force1 electricity can pass through just about anything--even jump gaps6 ,electricity1 like water1 flows along the easiest paths4 ,it is always trying to get to the ground4 ,the earth attracts it4 ,it stays on the wires unless a person1 a wet branch1 or some other conductor gives it a path to the ground4 ,do not touch any wire which might be carrying electricity4 ,play ,it ,safe ,if you should touch a hot wire accidentally and are standing on a dry piece of wood1 the conducting pathway to the ground is not good and the electricity may keep running along its wire4 ,but do not touch some other conductor with another part of your body4 ,this would complete a circuit through your body and would be very dangerous4 ,always make sure there is plenty of good insulation material or plenty of distance between you and anything which might be carrying electricity4 ,remember1 too1 insulation is of little use when it is wet4 ,dew1 mist1 rain1 condensation1 a damp floor can change the whole picture4 ,if you understand electricity and how it acts1 you'll be safe enough1 because you won't take chances or expose yourself to injury4 ,electrical ,terms ,alternating ,current--,usually referred to as ,,ac1 alternating current is current which reverses its direction of flow at regular intervals1 #fj times a second4 ,direct ,current--,,dc current flows only in one direction4 ,battery current is ,,dc4 ,ampere--,amperes are units by which the rate of flow of electrical current 7electrons7 is measured4 ,an ampere is #f4c billion electrons passing one point in a circuit1 in one second4 ,this compares with the way the flow of water is measured in gallons per second4 ,volts--,a volt is a unit to measure the tendency of electrons to move when they are shoved4 ,voltage is the amount of push behind the electrons4 ,it's like water pressure in a pipe4 ,home power lines carry #aae volts 7#aaj to #abj volts74 ,for appliances such as electric stoves1 washers and driers1 a second #aae-volt line should be added1 giving #bcj volts 7#bbj to #bdj volts74 ,watts--,watts equal volts times amperes4 ,light bulbs1 electric irons and other appliances are usually marked with the voltage they require and the number of watts4 ,kilowatts--,your electric bill usually reads in kilowatt hours4 ,a kilowatt is #ajjj watts4 ,a kilowatt hour equals #ajjj watts used for #a hour4 ,one kilowatt equals about #a-a_/c horsepower4 ,a kilowatt is usually indicated by kw and a kilowatt hour by kwh4 ,circuits--,a closed circuit is one in which the electricity is flowing1 lighting a light1 running a motor1 or some other appliance4 ,the circuit runs all the way from the place the electricity is being generated to your home1 through the appliance or light bulb1 and back to the generator4 ,circuits are opened and closed by switches4 ,when the circuit is opened1 the electricity stops at the switch4 ,before working on a switch1 socket1 fuse1 or any part of the wiring be sure to open the main switch4 ,the main switch is usually at the fuse box or near it4 ,appliances should be disconnected when you work on them4 ,everyone in the family should know where the main switch is so it can be pulled in case of accidents1 fire1 flood1 or windstorm damage4 ,fuses and ,circuit ,breakers--,these are the safety valves of your electrical system4 ,the different electrical circuits in your home are meant to carry only certain amounts of electricity4 ,some carry only #ae amps1 others can carry #bj or more4 ,they are marked to show capacity4 ,when a fuse burns out or a circuit breaker opens1 look for an overload of lights and appliances on the circuit before you try to replace the fuse or close the circuit breaker4 ,without these safeguards1 the overloaded electric line will heat up and may start a fire4 ,even if no fire starts1 electricity will be wasted and the homeowner will be paying for electricity that's doing no good4 ,remember3 ,if you ever have to replace a fuse1 pull the main switch first4 ,keep a flashlight handy in your house4 ,it seems that fuses usually blow at night1 and it doesn't pay to stumble or fumble around electric wires in the dark4 ,,what ,,to ,,do3 ,make ,a ,circuit ,board ,so that you can show others how electricity travels from here to there1 and how it behaves under different conditions1 make an electric circuit board4 ,materials ,needed3 ,piece of #c_/d board about #d x #f l-l_/#b-volt ,no4 #f dry cell battery ,two pieces of bell wire1 each #bd long1 one black1 one white ,two #aj-penny box nails 7#c7 ,three #c-penny box nails 7#a7 ,two small screws or carpet tacks ,two #b-;inch rubber bands ,two miniature sockets with solder terminals ,two l-l_/#b-volt flashlight bulbs ,tools ,needed3 ,ruler1 pencils1 hammer1 pliers or vise4 ,making the ,board3 #a4 ,lay out the board with a pencil and ruler as indicated in ,figure #a4 #b4 ,bend the three-inch nail as shown in ,figure #b1 using pliers1 vise and hammer4 #c4 ,pound the one-inch nails into the board for a half-inch at points ,a1 ,c1 and ,d4 ,use the three-inch nail to make a hole a half-inch deep at ,b4 ,put the crank nail in this hole and pound in a little farther4 ,attach the lamp socket brackets at ,e and ,f4 ,stretch the rubber band as in ,figure #c4 #d4 ,lay out the electricity path1 the circuit 7,figure #c74 ,use the black wire for the positive side of the circuit 7the center pole of battery74 ,twist it around the switch crank ,b1 and the center pole of battery4 ,run another piece to the outside terminal of bulb socket at ,e4 ,run white piece to negative pole of battery from the other terminal at ,e4 ,illustration3 ,figure #a 7,circuit ,board7 ,illustration3 ,figure #b 7,switch7 #e4 ,close the switch4 ,the rubber band should hold the switch nail tightly against nail at ,c4 ,does the bulb light8 ,if it doesn't1 check the connections4 ,now you have a circuit--a closed circuit when the electricity runs all the way from the positive pole to the negative pole4 ,the black wire is the hot side1 the live wire1 because it carries the full load of the battery up to the bulb4 ,remember1 battery current is direct current1 ,,dc4 ,in the case of alternating current1 ,,ac1 such as most homes and buildings use1 the electricity flows in first one direction and then the other4 ,illustration3 ,figure #c 7,closed ,circuit7 ,parallel ,wiring ,to make this circuit hookup1 attach another white wire to the negative pole of battery and a terminal of the second flashlight bulb4 ,run a black wire from the other terminal to the switch terminal at ,c 7,figure #d74 ,close switch4 ,both bulbs will light4 ,trace the circuit4 ,electricity is going equally to each bulb1 the same amount that went to the single bulb4 ,the difference is that the battery will last only half as long4 ,it's like a pail of water with two open spigots4 ,the pail empties twice as fast as it would with just one spigot open4 ,this type of wiring is called parallel wiring4 ,if one bulb is unscrewed1 the other will stay lit4 ,figure #d 7,parallel ,wiring7 ,series ,wiring ,to do this1 run the negative wire to one terminal of the second bulb and attach a wire from the other terminal to a terminal of the first bulb4 ,the other terminal connects with the switch at ,c 7,figure #e74 ,this is series wiring4 ,if one bulb is unscrewed1 the other will fail to light because the circuit is broken for both4 ,anything that breaks the circuit has the effect of opening the switch4 ,illustration3 ,figure #e 7,series ,wiring7 ,show there is a circuit through the bulb by screwing and unscrewing it4 ,also1 jump the socket by running the wire from ,c to the other terminal of the bulb at ,e while it is unscrewed4 ,bulb at ,f will light4 ,trace this circuit4 ,,suggested ,,demonstrations ,using the ,circuit ,board1 you can give many demonstrations of the way electricity flows1 works and behaves4 ,water ,and ,electricity ,to help others understand electricity better1 draw a water system on an electric circuit board paralleling the circuit4 ,for the battery show a water tank1 pipes instead of wires1 faucets instead of switches4 ,somewhere on the board paste a comparison of electrical terms with terms used in describing water1 such as the following3 ,wire equals ,pipe ,volts equal ,pressure ,amperes equal ,rate of ,flow - gallons per second ,watts equal ,pressure times ,rate of ,flow ,switch equals ,faucet ,current equals ,flowing ,water ,show how to figure the wattage that a circuit protected by a #ae ampere fuse can handle4 ,do it with actual things or cut-out pictures of light bulbs1 irons1 toasters1 coffee-makers1 etc4 ,you know that ,amperes times ,volts equal ,watts4 ,if the voltage is #aae1 a #ae amp circuit can handle #aae volts times #ae amps1 or #agbe watts4 ,the name plates on electric motors indicate the amperage at full load4 ,you can convert this to watts1 of course1 by multiplying amperage by the line voltage4 ,motors require an additional amount of electricity when they start4 ,you need to allow for this fact1 so fuses will not blow or circuits trip when a motor is turned on4 ,you will learn more about this when you study electric motors4 ,for ,more ,information ,your leader has many other sources of information about electricity and demonstrations you can perform4 ,ask him4 ,also1 libraries have many books about electricity and its history1 which are very interesting and useful4 ,maybe you can find an electrician1 someone from your power supplier1 or an equipment dealer who will talk to your club on electricity or electrical safety4 ,what ,did ,you ,learn8 7,underline the correct answers then discuss in the group47 #a4 ,in a water pipe system water flows4 ,in an electrical circuit 7electrons7 7atoms7 7charges7 flow4 #b4 ,electricity or electrons flow 7easier7 7harder7 7about the same7 in a conductor than in an insulator4 #c4 ,rubber is a good 7conductor7 7insulator7 7ground74 #d4 ,the most common material used as an electrical conductor is 7glass7 7silver7 7copper74 #e4 ,the unit of electrical pressure or push is the 7ampere7 7volt7 7watt74 #f4 ,the rate of flow of electricity is measured in 7gallons7 7amperes per minute7 7amperes74 #g4 ,volts times amperes equals 7watts7 7kilowatt hours7 7alternating current74 #h4 ,a dry cell battery 7stores7 7makes7 7uses7 electrical energy4 #i4 ,in a parallel circuit the electricity has 7one7 7two or more7 7no7 paths to travel4 #aj4 ,in a series circuit with two bulbs and a switch the bulbs are 7brighter7 7dimmer7 7the same7 as when they were in the parallel circuit4 ,,lesson ,,no4 ,b-#b ,credit ,points #d ,,tools ,,for ,,electricians ,who goeth a borrowing ,goeth a sorrowing ,few lend 7but fools7 ,their working tools ,tusser #aebd-aehj ,whenever a job comes up1 it saves time and trouble when you have the right tools and they are all where you can find them4 ,electrical work takes some special tools and some everyday tools4 ,if you have ever watched a good electrician at work1 you've seen how neatly he stores his tools in a box so every one of them is handy4 ,when a lineman climbs a pole1 he has his regular tools in a holster on his belt4 ,special tools are kept in a box in racks in the repair truck1 all ready for instant use4 ,wouldn't you like to have electrician's tools all handy1 ready for use1 and know how to use them properly8 ,basic ,tools for ,electrical ,work ,knife ,a good knife with a sharp blade is one of the most useful tools4 ,a camper's or electrician's type knife is probably best because it has other useful parts besides the cutting blades--a screwdriver or punch1 for instance4 ,of course1 you'll never use the cutting blades as a screwdriver4 ,this knife should be kept clean1 dry1 sharp1 and free from rust4 ,put a little oil on the joints from time to time4 ,remember1 ,never whittle toward you and you'll never cut yourself4 ,pliers ,a pair of electrician's pliers should be part of your kit4 ,wrap the handles with plastic insulating tape4 ,even though you're not going to work on hot electric lines1 it pays to play safe4 ,later on1 as you learn more about electricity1 you'll want a pair of needle-nose pliers for the fine work4 ,screwdrivers ,you'll want a screwdriver which has true corners4 ,a #d to #f inch plastic handled screwdriver with a narrow blade is best4 ,you'll probably need more than one size to fit the various size screws you'll be turning4 ,screwdrivers are easily damaged if you try to use them as chisels and pry bars1 or use them in screw slots which are too large for the blade4 ,you can be hurt by the screwdriver if you try to screw or unscrew things you are holding in your hand4 ,keep your free hand away from the end of the screwdriver4 ,place the work on a bench or where it can be handled easily4 ,soldering ,iron ,a good #ajj to #bej-watt electric soldering iron will be useful4 ,later on you may want to buy a soldering gun1 but unless you are doing a lot of soldering it won't be necessary4 ,a supply of resin-core electrician's solder will be needed4 ,acid-core solder reacts with copper and in time causes a bad splice4 ,tape ,once it was necessary to use two types of tape on splices--rubber tape with friction tape over it4 ,now there is a plastic tape on the market which takes the place of both and has good insulating quality4 ,it is called electrical tape1 or plastic tape1 and resists water1 oils 7which would damage rubber tape71 and acids4 ,you'll need a lot of tape in your electrical work1 so keep a roll on hand4 ,other ,tools and ,equipment ,as you go along in electrical work1 you'll be adding tools and other equipment1 such as a trouble light and maybe an ammeter or voltmeter4 ,other tools you'll want to add will be a ,phillips screwdriver1 open end wrenches1 a crescent wrench1 small hack saw1 hand drill and bits4 ,you'll also be using some regular carpenter's tools such as hammers1 saws1 and so on4 ,unless you use them frequently1 you don't need to keep them in your electrical kit4 ,it's a good idea to start acquiring a supply of electrical parts--lengths of wire1 fuses1 switches1 sockets1 plugs1 and other items that will come in handy4 ,there are parts you can salvage from old lamps1 motors1 and other equipment4 ,such a collection can be a real treasure chest when you need a part in a hurry4 ,but be sure to throw away all faulty parts4 ,illustration3 ,figure #a4 ,completed tool chest4 ,,what ,,to ,,do3 ,build a ,tool ,chest ,to keep your tools always ready for use1 a tool chest will be very handy4 ,it's the #d-;,h way to work4 ,you'll be surprised how much easier it makes a job when you have your tools1 various parts and repair equipment all in one place4 ,you can make the chest 7,figure #a7 with a saw1 plane1 screwdriver1 pencil1 ruler or carpenter's square1 and hammer4 ,materials ,you'll ,need3 ,a piece of lumber #a by #aj by #h feet long4 7#a lumber is actually only #c_/d thick--this is the thickness you'll be working with47 #b small hinges1 with wood screws #a small hasp1 with wood screws #b small handles with wood screws1 or one large handle #a small chain1 #aj to #ab long ,some ,no4 #f penny finishing nails or wood screws about the same length ,making ,the ,chest3 #a4 ,cut your lumber into the following pieces3 #a piece #aj x #ah for top #a piece #h-a_/b x #af-a_/b for bottom #b pieces #f x #h-a_/b for two ends #b pieces #f x #ah for front and back #b4 ,lay out pieces as shown in ,figure #b4 ,illustration3 ,figure #b ,then1 set up the two end pieces and nail to bottom section4 ,refer back to ,figure #a as you go along to see that box is shaping up as shown4 ,nail the front and back sections to the ends along the bottom4 ,wood screws can be used instead of nails4 #c4 ,lay the top in place and attach hinges to the back side1 about two inches in from each end4 #d4 ,attach one part of hasp to the top1 and the other part to front board in center4 ,fasten the handles to each end4 #e4 ,attach chain to the top and front so the top will stay open when chain is fully extended4 ,now you can invent your own improvements for your chest4 ,you can paint it1 put your name on it1 and your club emblem and name if you wish4 ,you can put a rack on the inside of the cover to hold your work sheets and other booklets and materials4 ,you can install special slots or straps to hold each tool in its place along the sides of the box4 ,maybe you will want to put some partitions in the box to separate various electrical equipment such as wires1 fuses1 switches1 and plugs4 ,a ,working ,kit ,an accessory which you may want to add to your tool chest is an apron or holster to wear when you are moving around on the job4 ,an apron can be made of a size of cloth about #ah by #bj inches4 ,it should be folded up from the bottom1 and sewn to fit the number and size of tools you have4 ,figure #c shows such an apron4 ,illustration3 ,figure #c4 ,apron4 ,you can make a lineman's holster in the same way1 using plastic or soft leather4 ,merely make belt loops by cutting on the dotted lines4 ,a snap fastener will hold the flap over the tools so they won't fall out4 ,illustration3 ,figure #d4 ,lineman's ,holster4 ,demonstrations ,you ,can ,give ,show and tell others the proper handling1 care and use of tools4 ,show and tell how to build an electrician's tool kit4 ,for ,further ,information ,ask your power supplier or an electrician to tell the club about the various tools of the electrician's trade and demonstrate them4 ,ask your leader how to get exhibit material or information about electrical tools and their use and then tell the club about them4 ,,lesson ,,no4 ,b-#c ,credit ,points #c ,,rewire ,a ,,lamp--,,be ,a ,,lamp ,,detective ,illustration3 ,the ,line-,up ,of ,lamp ,suspects ,one of the duties of a law officer is to prevent crime4 ,it's that way with the lamp detective4 ,you can become one4 ,in the average home there are lamps about to commit the crime of shocking people1 starting fires1 and stealing electricity4 ,some are refusing to do their job well and some are no-goods1 sitting in closets or attics1 doing nothing4 ,you can put these lamps to working again safely and well4 ,become the lamp expert in your family4 ,what's ,in ,a ,lamp8 ,a lamp gives light for comfortable and convenient use in the home4 ,it consists normally of a stand1 switch1 cord1 lampshade holder1 and shade4 ,some lamps have diffusing bowls which reduce glare and shadows4 ,the most common fault found in an old lamp is in the cord1 but sometimes the switch or the wiring in the lamp is bad4 ,look over all the lamps in your home and find the ones needing to be fixed4 ,,what ,,to ,,do--,rewire ,a ,lamp ,somewhere around your house you can probably find a lamp that is no longer used or needs repairing4 ,you can make it useful again and at the same time learn how to wire a lamp4 ,materials ,needed3 ,tools3 ,pocket knife1 small or medium screwdriver1 and pliers 7electrician type is best74 ,new ,lamp ,cord3 ,for each lamp to be rewired1 you'll need #f feet of cord plus the length of wire within the lamp stand4 ,lamp cord wire comes in two sizes1 ,no4 #ah and ,no4 #af ,,awg 7,american ,wire ,gauge74 ,no4 #ah is smaller than ,no4 #af1 but is adequate for most lamps4 ,cords are made with surface coverings of several different materials3 braided cotton1 rayon or silk1 and molded rubber or plastic4 ,braided cord is decorative1 but rubber or plastic is easier to work with and is usually more desirable4 ,switch3 ,if the switch is bad1 get a new one4 ,socket switches are made with push-through1 turn-knob1 or pull-chain controls4 ,the pull-chain type is seldom used on modern table or floor lamps4 ,your lamp may have a separate push-switch in the base4 ,in this case1 get the same kind for replacement4 ,some switches are #c-;circuit switches for use with high1 medium1 and low-light bulbs4 ,plug3 ,plugs are made of various materials1 mostly hard rubber or molded plastic4 ,some have a shank or handle for better grasping4 ,this type is more desirable4 ,the plug on the old cord may be good1 and if so1 may be used on the new cord4 ,how ,to ,do ,it3 #a4 ,if the plug on the old cord is good and you plan to use it1 remove it from the old cord4 #b4 ,measure and cut a new lamp cord equal to the length of the cord within the lamp1 plus #f feet4 #c4 ,pass one end of the new cord through the center of the plug4 ,strip #b inches of the fabric insulation off cord1 or in case of a rubber cord1 split cord back two inches4 ,be sure no bare wire shows in long split section 7,figure #a74 #d4 ,use knife to strip insulation off wire for #c_/d on end of each cord4 ,be careful4 ,don't cut yourself4 ,don't cut wires4 ,use a light touch1 slope the knifeblade and slice with knife edge away from you 7,figure #a74 ,illustration3 ,figure #a 7,ready to ,wire ,plug7 #e4 ,twist exposed strands of each wire tightly to make a good conductor1 and place each conductor around its proper terminal in the direction in which the screw tightens 7,figure #b74 #f4 ,tighten screws on terminal posts4 ,pull cord until slack is out4 ,lay aside until ready to attach to lamp4 ,illustration3 ,figure #b 7,attaching ,cord to ,plug7 #g4 ,remove lamp shade1 shade-holder1 bulb1 and diffusing bowl1 if there is one4 #h4 ,separate the metal shell of socket from its cap by pressing on shell at place marked press1 and pull socket from cap4 #i4 ,pull on socket body to get some slack in lamp cord4 ,loosen screws and detach cord4 ,pull cord out through base of lamp4 ,you can splice new cord to the old one and use the latter to string the new wire4 #aj4 ,pass the new cord up through the lamp base and socket cap1 tie a simple half-hitch knot in the cord to prevent strain on the terminals1 and attach wires to the terminals on the socket 7,figure #c74 ,if there is likely to be any strain on cord1 use an ,underwriters' knot4 ,twist strands and attach wire in direction in which screw tightens4 #aa4 ,pull slack out of cord in lamp so that socket rests in socket cap1 replace shell and reconnect cap4 ,be sure the fiber insulator is in the shell4 ,you'll feel or hear a click when the notches in shell are locked to the projections in the cap4 #ab4 ,replace bulb1 inspect carefully1 and test4 7,in floor lamps where the cord runs through the center post and out under the base1 the cord will last longer if it is fastened with tape so it doesn't rub edge of lamp base when lamp is moved47 #ac4 ,if the lamp has a porcelain socket1 simply disconnect the wires at the terminals1 remove the old wire and connect the new one4 ,illustration3 ,figure #c 7,socket and ,switch ,assembly7 ,what ,did ,you ,learn8 ,underline correct answers then discuss in the group4 7,there may be more than one correct answer47 #a4 ,the part of the lamp that usually wears out first is 7the socket7 7the cord7 7the plug74 #b4 ,lamps that waste electricity are those which have 7bad wiring7 7frayed cords7 7dirty shades or bulb74 #c4 ,to unplug a lamp you should grasp 7cord7 7plug7 firmly and pull4 #d4 ,wire in lamp cord usually comes in sizes #af or #ah4 ,size #af is the smaller 7true7 7false74 #e4 ,in fastening wire around a terminal post it should go around in a 7clockwise7 7counter-clockwise7 direction4 #f4 ,when the switch on a lamp is turned off1 the electricity only goes as far as 7the wall plug7 7the switch74 #g4 ,an ,underwriters' knot should be used 7only when there is room for it in the plug7 7whenever there is likely to be strain on the cord1 even if you have to replace the plug with a larger one74 ,,suggested ,,demonstrations ,show how to inspect a lamp and its cord4 ,you might tie tags on the cord and lamp at points of danger or failure--at the plug1 wear points next to lamp base1 bad sockets4 ,demonstrate the process of repairing a lamp cord1 socket and plug4 ,make a board display of the parts of the lamp socket showing cord attached4 ,make a display of the types of lamp cords and plugs in common use4 ,using two lamps1 one with clean bulb and shade1 the other dusty1 show how the former gives more light4 ,for ,more ,information ,lamps have an interesting history4 ,look it up in your local library4 ,ask someone from your power supplier or electric dealer to talk to the club about the different kinds of lamps4 ,your leader has or can get additional information on lamps1 if you wish4 ,illustration ,what ,did ,you ,exhibit ,what ,did ,you ,demonstrate ,,lesson ,,no4 ,b-#d ,credit ,points #c ,,make ,a ,,trouble ,,light4 ,a handy piece of equipment in the home and on the farm is a heavy-duty extension cord with a shielded light and a side outlet on it4 ,when you want to work on the car or tractor in the yard at night1 the trouble light is better than a flashlight4 ,you can use it both for light and as an extension cord4 ,it is safer than matches or a lantern1 especially around the garage or barn4 ,it is easy to make a trouble light1 and it gives you good practice in electrical work4 ,of course you can buy one1 but you wouldn't have the fun of making it nor would it suit your needs4 ,trouble lights are not for permanent use--they're for emergency use and to provide light or electricity in places where they are seldom needed4 ,when you find a trouble light being used as permanent wiring1 that's the place to install an outlet4 ,what ,size ,cord8 ,choose the right kind of cord4 ,what length will be best for your various uses8 ,a cord too long may be bothersome to use and store4 ,what will be the heaviest load you are likely to put on the cord1 in amperes8 ,check appliances you may want to connect to it4 ,no4 #af wire can carry #aj amperes safely for a distance of #ej feet1 while ,no4 #ah can carry only up to #g amperes for a distance of #dj feet4 ,you'll want a hard service cord1 called ,s1 ,,st1 or ,,so-type cord by electricians4 ,junior hard service cords1 known as ,,sj1 ,,sjt1 or ,,sjo1 are fine for lighter duty4 ,cord1 ,plug and ,guard ,a rubber-handled socket should be used for safety and to withstand hard knocks4 ,it should have a switch on it1 preferably a push switch in a recess in the handle4 ,the connector or attachment plug should be of rubber or solid plastic and have a metal cord grip fastened to it4 ,this grip will hold the cord firmly and prevent strain on the terminal connections4 ,illustration3 ,finished ,trouble ,light ,get a good lamp guard4 ,if the wire is too light1 it may bend and break the bulb when hit or dropped4 ,for the lamp itself1 get a rough service lamp4 ,an ordinary lamp won't last long with rough usage4 ,how to ,make the ,trouble ,light ,tools ,needed3 ,your #d-;,h electrician's kit or screwdriver1 knife and soldering iron ,materials ,needed3 #a4 ,about #bj feet of #b-wire1 ,no4 #af heavy duty 7hard service7 #b4 ,a rubber-handled socket with switch and a side outlet #c4 ,a shielded lamp guard ,illustration3 ,materials ,needed #d4 ,a good connector plug cap1 preferably with a clamp-type grip for the cord #e4 ,a rough service lamp bulb #f4 ,solder and flux ,steps to ,take3 #a4 ,remove about #b inches of the outer covering of cord at one end4 #b4 ,separate the wires and cut away the filler material4 #c4 ,remove #c_/d inch of the conductor insulation from the end of each wire and tightly twist the strands together to form a firm conductor4 ,be careful not to cut any of the fine wires4 ,ends may be soldered4 #d4 ,slide the plug in position on the cord4 #e4 ,if there is no cord grip1 tie the underwriters' knot 7,figure #a74 ,if there isn't room enough1 make an ,s loop by passing the wires around the prongs before fastening them to the terminal screws as explained in the next step4 #f4 ,loop the bare part of the wire around the screw in the direction the screw is turned to tighten 7clockwise direction74 ,this will prevent the wires from being forced out from under the head of the screw as it is tightened4 ,now repeat with the second wire1 wrapping it around the other prong of the plug4 ,connecting the socket4 #a4 ,separate the parts of rubber-handled socket 7,figure #b74 #b4 ,prepare the other end of the cord as in steps #a1 #b1 and #c above4 #c4 ,insert the cord through the rubber handle and socket guard4 #d4 ,tie the holding knot 7underwriters' knot7 as explained in ,step #e4 #e4 ,connect wires to terminal screws and assemble the rubber-handled socket4 #f4 ,screw in the rough service lamp and test your cord4 #g4 ,put the shielded lamp guard on the socket and tighten the holding clamp until it is firmly in place4 ,you are now ready to use or demonstrate your trouble light4 #h4 ,after you've made your trouble light1 decide on a good place to keep it where it will be handy for use4 ,loop it carefully and hang it over a wooden dowel rather than a nail4 ,it will last longer4 ,illustration3 ,figure #a ,tying an ,underwriter's ,knot ,illustration3 ,figure #b ,disassembled ,light ,what ,did ,you ,learn8 7,underline correct answer7 #a4 ,a ,junior ,hard ,service ,cord is known as an 7,,so-,type7 7,,sjo-,type7 cord4 #b4 ,you disconnect a cord by 7jerking it from the socket7 7grasping plug and pulling it out74 #c4 ,brass sockets are unsafe because 7they break too easily7 7the exposed metal can cause short circuits74 #d4 ,rubber-covered cord is safer for emergency cords than fabric because 7it will stretch7 7it will insulate and protect the wires inside74 #e4 ,in a trouble light 7any kind of bulb will do7 7a rough service bulb is best74 ,ideas for ,demonstrations and ,exhibits #a4 ,show how to make your trouble light and a method of storing it4 #b4 ,show a safe trouble light1 and an unsafe trouble light with danger points marked4 #c4 ,show cutaway pieces of different types of cord4 ,for ,more ,information ,ask your power supplier1 county highway engineer1 police official or leader to tell you about various types of portable emergency lights and their uses4 ,,lesson ,,no4 ,b-#e ,credit ,points #e ,,what ,,makes ,,motors ,,run ,what makes an electric motor run8 ,can you make an electric motor that will run8 ,certainly you can1 and by doing so you'll learn why it runs4 ,it won't be mysterious any more and you'll be ahead of all the millions of people who use motors every day and never know why or how the motor converts electrical energy into useful power4 ,illustration ,motors ,are ,magnets ,you know how one end of a compass needle always points to ,north4 ,no matter how you turn the compass1 the same end of the needle always swings to the ,north4 ,the earth itself and that small compass are both magnets 7,figure #a74 ,each has a ,north pole and a ,south pole4 ,around the poles of each there are magnetic fields1 invisible lines of force that attract and repel4 ,illustration3 ,figure #a4 ,the same end of the compass needle always points to the earth's magnetic ,north ,pole4 ,the ,n poles repel each other and so do the ,s poles4 ,the ,n and ,s poles attract each other4 ,in other words1 opposite poles attract2 poles that are alike repel each other4 ,lay #b bar magnets on a table side-by-side4 ,if both ,n poles are at one end1 they'll repel each other and almost flip around until there's a ,n pole lying next to a ,s pole 7,figure #b74 ,illustration3 ,figure #b4 ,small bar magnets laid side by side move so that the ,north pole of one is near the ,south pole of the other4 ,now suppose we place one of the bar magnets on the table4 ,the other1 we'll fix on a pivot so it can spin around4 ,this one we'll move so its ,n pole almost touches the fixed magnet's ,n pole4 ,as soon as we release it1 the movable magnet will spin around so its ,s pole will be near the ,n pole of the stationary magnet4 ,that's an electric motor--almost4 ,illustration3 ,figure #c4 ,a movable bar magnet pivots so its ,south pole is near the ,north pole of a stationary magnet4 ,it's not quite a motor because the rotating magnet will just move as far as it has to in order to get the opposite poles together4 ,you might be able to cause the movable bar magnet to make turn after turn4 ,you could do this by turning the fixed magnet quickly end for end4 ,this wouldn't be very practical as a motor4 ,we ,can ,improve ,it ,if we could change the pole on one end of the rotating magnet just as soon as it reaches the attracting pole1 it could make a complete circle4 ,in doing that1 the pole at the near end of the rotating magnet would be repelled by the stationary magnet and pushed away4 ,as soon as the opposite end of the rotating magnet would come into the magnetic field1 it would be drawn to the stationary magnet4 ,in order to keep the motor running1 we would have to constantly change the poles at each end on every half revolution4 ,we ,need ,an ,electromagnet ,we can't reverse the poles on simple bar magnets1 but we can on electromagnets4 ,we can make one by wrapping a wire several times around an iron core to form a coil4 ,this magnet will also have a ,n and a ,s pole when connected to electrical current4 ,the big difference is that the poles can be changed instantly by reversing the current in the wire4 ,switching ,poles ,automatically ,the rotating electromagnet will have to be connected to the #b wires through which we pass the current4 ,since it's rotating on a center shaft1 we can't have a solid connection4 ,instead we have to extend the wires from the coil out along the shaft and let the electric contact be made with brushes which touch the wires along the shaft4 ,illustration3 ,figure #d4 ,a rotating electromagnet changes poles as contacts are made first one way1 then the other4 ,this is a simple way to reverse the current in the coil of the electromagnet4 ,increasing ,efficiency ,instead of using only one pole of a stationary magnet1 we can use both4 ,this is done by shaping the stationary magnet around the path of the rotating electromagnet4 ,this way we have the benefit of the attracting and repelling forces from both poles4 ,the effect is doubled4 ,we can also wrap wires around this circular iron and make an electromagnet of it4 ,but when we wire this magnet we use no brushes because we want the current to flow in one direction only4 ,the stationary electromagnet is called the field4 ,the rotating electromagnet is the armature4 ,,what ,,to ,,do3 ,make ,a ,motor ,tools ,needed3 ,pocket knife1 hammer1 vise 7or #b pairs of pliers74 ,materials ,needed3 #a roll of ,no4 #bd enameled wire #a roll of electrician's tape #c - #d 7#bj-penny7 nails #d - #b-a_/b 7#h-penny7 nails #d - #c brads 7#aj penny7 ,wood board for motor base #b staples or #d small brads #b tacks #b - #c volt dry cell batteries 7or a #f volt transformer74 ,step ,no4 #a-;,armature ,wrap about #a-a_/b of a #d nail with two layers of tape4 ,this will be the shaft4 ,the iron core will be made of two pairs of #b-a_/b nails4 ,wrap tape around each pair with heads and points alternated4 ,center both pairs on each side of the shaft4 ,place them about #a from the head of the shaft nail4 ,wrap them together with two layers of tape from tip to tip4 ,start at the shaft and wind ,no4 #bd enameled wire to one end and back4 ,then do the same on the other end4 ,always wind in the same direction4 ,leave #f of spare wire at start and finish4 ,step ,no4 #b-;,commutator ,scrape all insulation off the ends of the wire4 ,bend the bare ends back and forth as shown4 ,lay them flat over the taped shaft-one on each side of the shaft4 ,hold the commutator down with narrow strips of tape4 ,wrap tightly near the core and at the opposite end4 ,step ,no4 #c-;,field ,make the core by bending two #d nails in the middle at right angles4 ,space the heads about #c apart to form a horseshoe4 ,wrap together with two layers of tape4 ,wind about #djj turns of wire around the center4 ,leave #d of spare wire at start and finish4 ,attach to wood base with staples at each end of the wire4 ,small brads1 bent over1 will do just as well4 ,step ,no4 #d--;,armature ,supports and ,brushes ,scrape the insulation from the ends of two #f pieces of wire4 ,tack them to the base and bend them as shown to make brushes4 ,drive two pairs of #c brads into the base about #c-a_/d apart and in a line midway between the field poles4 ,wrap wire around the supports to form armature bearings4 ,scrape insulation off ends of wire from the field4 ,connect one end to a brush wire4 ,assemble ,as ,shown ,adjust the position of commutator and tension of brushes against it for best operation4 ,take the armature off the motor and connect the commutator wires to a dry cell battery4 ,test the polarity of each end of the armature with a compass4 ,switch the connections on the commutator and test again4 ,see how the compass needle changes direction8 ,with the armature still off1 connect the field coil directly to the dry cell4 ,test the polarity of each end of the field with the compass4 ,how can you reverse the polarity8 ,try it4 ,it's easy4 ,reassemble the motor again and start it4 ,push the field poles slightly out of alignment with the turning armature4 ,what happens to the motor's speed8 ,can you tell why8 ,this time1 push the field poles completely out of the way4 ,test the polarity of the armature as you slowly turn it by hand4 ,do you see what happens and why it does8 ,try to reverse the direction of rotation of your motor by reversing the connections at the battery4 ,what happens8 ,can you explain why8 ,demonstrations ,you ,can ,give ,make a display board showing the parts of the toy motor and explain how each part works compared with the parts of a commercial motor4 ,for ,further ,information ,there are several other types of toy motors you can build4 ,your club leader or power supplier can help you find information about them4 #a4 ,did your toy motor run8 #b4 ,did your motor speed up or slow down when you pushed the field poles out of line8 ,why8 #c4 ,what happens to the magnetic polarity of the armature when you turn it slowly by hand and check it with a compass8 #d4 ,how can you reverse the direction of rotation of your toy motor8 ,is there another way too8 ,what is it8 ,,lesson ,,no4 ,b-#f ,credit ,points #c ,,taking ,,care ,,of ,,electric ,,motors ,through the magic of electric motors1 much of our work is done faster and better at lower cost than we could do it without the help of the electric motor4 ,people who use motors and treat them properly have much more time for other work and for leisure time activities4 ,a #a_/d-;horsepower motor running quietly and steadily hour after hour will do the work of one man1 and operate all day for about #e cents without tiring4 ,on many jobs it will work without supervision1 turning on and off automatically1 as required4 ,it does this on water pumps1 in heating and cooling units1 and on fans and similar appliances4 ,all that a motor needs to do its work is electricity and a little care4 ,let's see what you can do to give proper care to motors in your home and on your farm4 ,you'll ,need ,a light oil 7,,sae #aj7 for motors of less than one horsepower and a slightly heavier oil 7,,sae #bj7 for larger motors4 ,see if you need grease for cups which may be on large motors4 ,if so1 be sure you use ball-bearing grease and not ordinary cup grease4 ,cotton waste or clean rags will be needed for wiping off the motors1 and a tire pump or vacuum cleaner for blowing out the dust or dirt4 ,illustration3 ,some motors have instructions for oiling on the name-plate4 ,,what ,,to ,,do #a4 ,first1 make a list of all the electric motors that work for your home4 ,you may wish to make a separate list for your farm buildings4 ,you'll probably be surprised at how many there are4 ,don't forget the sewing machine1 the refrigerator1 the freezer1 the vacuum cleaner and other small but important motors4 ,don't touch any motor that is running4 ,disconnect them before you touch them4 #b4 ,make a motor service chart with columns headed3 ,use1 ,location1 ,horsepower1 ,volts1 ,amperes1 ,service ,required1 ,date ,serviced and ,what was ,done4 7,see sample7 ,then list all the motors that require any servicing4 ,some will have the instructions on the motor or appliance2 the instruction booklet that came with the motor or appliance will also tell what servicing is required4 ,step #a4 ,plan the job4 ,start with the motors in the home4 ,then you can care for the motors on the farm4 ,step #b4 ,be sure that any motor on which you are going to work is disconnected4 ,then wipe the outside case clean with a cloth4 ,if the motor has openings in the end1 use a vacuum cleaner to suck out dust1 dirt or chaff4 ,a tire pump may also be used to blow out this dirt4 ,if you use compressed air1 be sure the pressure is not high as it may damage wiring inside the motor4 ,dust-proof motors should be used in dusty or dirty places4 ,step #c4 ,illustration3 ,if there are oil holes1 oil according to the manufacturer's instructions4 ,if there are no instructions1 remember a little oil goes a long way as far as motors are concerned4 ,motors of less than one horsepower require only #c or #d drops 7not squirts7 of oil every #c or #d months if the motor is used frequently4 ,too much oil can damage the motor4 ,it spoils the insulation4 ,if there are no oil holes or grease cups on the motor1 it is probably lubricated by means of grease sealed in the bearings at the factory1 or it may use greaseless bearings1 and does not need to be oiled or greased periodically4 ,indicate on your chart all motors which need periodic care and see that it is given according to schedule4 ,wipe away any excess oil or grease4 ,be sure oil holes are capped or covered4 ,step #d4 ,reconnect motor and run for a moment4 ,step #e4 ,record on the chart the date you serviced the motor and what was done4 ,what ,did ,you ,learn8 ,how many motors are there in your home8 ,on the farm8 ,how many motors need regular oiling or grease8 ,how many are less than one-horsepower8 ,,sae ,oil is used to oil motors up to #a_/b horsepower4 ,how much oil8 ,,sae ,oil is used for larger motors4 ,demonstrations ,you ,can ,give #a4 ,show how to clean a small motor4 #b4 ,explain proper lubrication of motors4 #c4 ,using the chart prepared in this work sheet1 give a talk about the motors that work for you-the job each one does1 which ones need oil or grease1 which need no attention1 and why1 etc4 #d4 ,use a homemade toy motor to explain what makes motors run4 #e4 ,show proper way to replace worn cord on a small motor4 ,for ,further ,information ,ask your county ,extension agent or #d-;,h leader for more literature on motors4 ,they can help you obtain a film or a speaker such as a power supplier1 a local electric dealer1 or electrical contractor to discuss motors4 ,also visit your public library and see a science teacher for more information on motors4 ,,electric ,,motors ,,service ,,chart ,sample ,use a table like the following to list the motors around your farm and home4 ---------------------------------------- ------------------------------ ,motor ,location ,h4,p4,volt ,amp ,service ,date ,serviced and ,use ,needed what was done ---------------------------------------- ------------------------------ ,food ,kitchen #a_/f #abj #d4d ,clean ,oil2 #i_/a-;,cleaned ,mixer cord needs w_/cloth4 ,repair repair ,oiled w_/#aj ,oil2 repaired cord ---------------------------------------- ------------------------------ ,tool ,farm #a_/d #abj #e4h ,clear1 oiling2 #aj_/f-;,cleaned ,grinder ,shop ,have switch w_/vacuum ,oiled #aj ,have switch oil4 #aj_/bj-;,had repaired switch repaired ---------------------------------------- ------------------------------ ,pump ,pump #a_/c #abj #g4b ,oiling1 #i_/bf-;,cleaned house cleaning w_/tire pump2 oiled w_/#aj oil ---------------------------------------- ------------------------------ ,,lesson ,,no4 ,b-#g ,credit ,points #d ,,reading ,,the ,,electric ,,meter ,there is no question but what electricity is one of the lowest cost services in the home and on the farm4 ,a few pennies worth of electricity will provide the power to run machines that take the place of a man or of several men working all day4 ,however1 we all like to know what things cost4 ,sometime you may have to decide between different methods--man1 horse1 gasoline engine or electric motor power4 ,then you'll want to know how to figure the cost of electricity1 as well as the cost of the original equipment4 ,first of all1 you should know how to read an electric meter4 ,reading a ,meter ,electric meters read in kilowatt hours1 just as a water meter reads in gallons and a gas meter in cubic feet4 ,a kilowatt hour is the electrical energy consumed by #ajjj watts of electricity used for one hour4 ,ten #ajj-watt light bulbs burning for one hour would use one kilowatt-hour--one kwh4 ,illustration3 ,figure #a4 ,some meters give the reading directly1 like the mileage total on a speedometer4 ,some meters are read directly1 as shown in ,figure #a4 ,the more common type has four dials which are read from right to left--just the opposite from the way things are usually read4 ,the hand on the extreme right turns clockwise1 the next hand turns counter-clockwise1 the next clockwise2 the last hand on the left turns counter-clockwise4 ,the first dial on the right can register up to #aj kilowatt-hours2 the second up to #ajj kwh2 the third1 to #ajjj kwh2 the fourth1 to #aj1jjj kwh4 ,after that1 the meter starts over again4 ,to take a reading you must read all four dials of the meter1 from right to left4 ,illustration3 ,figure #b4 ,meter dials are read from right to left4 ,to read each dial1 you use the number last passed by the dial hand4 ,this may not be nearest the hand4 ,for instance1 if the pointer has passed #f and is almost on #g1 you read it as #f4 ,write down the figures in the same order you read the dial1 from right to left4 ,practice reading the meters shown in ,figure #c on the following page4 ,what's ,your ,electric ,bill8 ,meters aren't set back each month when the meter reader comes around4 ,the difference in the readings from one month to the next shows how many kilowatt-hours have been used4 ,if you know your electric rates1 you can figure your bill by yourself4 ,your power supplier will furnish you with a rate schedule on request4 ,illustration3 ,figure #c4 ,see if you can read the above correctly4 ,the answers are shown in a box on the next page4 ,it will be interesting to you to find out how much it costs to operate the various electric appliances in your home4 ,a sample rate schedule is shown in ,figure #d4 ,illustration3 ,figure #d4 ,sample rate schedule4 ,note that as the use of electricity increases1 the average cost per kwh is reduced4 ,estimating ,operating ,costs ,to find the cost of operating any single appliance1 three steps are necessary3 #a4 ,learn the wattage of the appliance4 #b4 ,estimate how many hours the appliance is used4 #c4 ,find its operating cost4 ,to ,find ,wattage3 ,watts1 you know1 are the measure of electrical power4 ,they are the product of voltage 7pressure7 times amperes 7rate of flow74 ,volts times ,amps equals ,watts4 ,the nameplate on the appliance will give the voltage required for proper operation as well as either amperage or watts4 ,if it gives wattage1 you have the information you want4 ,otherwise you must multiply volts times amps to get the wattage4 ,when voltage is given as #aaj-abj1 use #abj as your voltage4 #abj volts is nominal today4 ,how ,much ,will ,you ,use8 ,now that you know the wattage of the appliance1 multiply this figure by number of hours the equipment operates in one day4 ,divide this by #ajjj to get the kwh4 ,now multiply the result by the number of days the appliance is used each month4 ,this tells you the number of kwh used by the appliance during the month4 ---------------------------------------- ----- ,example ,no4 #a ,yard ,light3 #cjj-watt lamp ,amount of use3 #c hours per night4 ,multiply lamp wattage times hours of use per night to get watt-hours per night4 #cjj times #c #ijj watt-hours per night4 ,divide watt-hours by #ajjj to get kwh per night4 #ijj divided by #ajjj 4#i kwh per night4 ,multiply kwh per night times #cj to get kwh per month4 4#i times #cj #bg kwh per month4 ,if the yard light is used #c hours per night1 it consumes #bg kwh per month4 ---------------------------------------- ----- ,example ,no4 #b ,coffee ,maker3 #abj volts1 #eej watts 7from nameplate7 ,amount of use3 #a_/b hour per day4 ,multiply wattage of coffee maker times hours of use per day to get watt-hours per day4 #eej times #a_/b hour #bge watt-hours per day4 ,divide watt-hours by #ajjj to get kwh per day4 #bge divided by #ajjj 4#bge kwh per day4 ,multiply kwh per day times #cj to get kwh per month4 4#bge times #cj #g4bej kwh per month4 ,if the coffee maker is used l_/#b hour daily1 it consumes #g4be kwh per month4 ,calculate ,operating ,cost ,per ,month ,now that you know the number of kilowatt hours an appliance uses1 go to your rate schedule and your electric bill to see what the average kwh costs4 ,find the average cost of #a kwh by dividing the amount of your bill by the total number of kwh used in a month4 ,example3 #daj kwh used4 #ad4ce total monthly bill ,average cost per kwh equals #ad4ce divided by #daj kwh-#c-a_/b cents per kwh4 ,therefore1 the cost of operating the coffee maker for a month would be #c-a_/b cents times #g4be kwh--#be4d or #be cents4 ,cost of operating the yard light would have been #id4e or #ie cents a month4 7a7 #fceg 7b7 #aifc 7c7 #hiif ,correct answers to the meter readings shown on the preceding page4 ,adding ,low ,cost ,helpers ,you can see1 by looking at your rate schedule1 that the average cost per kwh gets lower as you use more electricity4 ,to find the cost of operating additional electrical equipment1 the cost per kilowatt hour is found from the last step in the bill--the lowest cost per kwh of the electricity you're now using4 ,sometimes power suppliers give special rates for such equipment as electric water heaters4 ,,what ,,to ,,do3 ,find the ,cost of ,operating ,electrical ,equipment ,make and fill in the blanks of a chart showing the electrical equipment you have and the operating costs per month4 ,make a chart for the home 7refer to chart one74 ,show the probable operating cost of equipment you might add to what you now have4 ,demonstrations ,you ,can ,give ,show how to read a meter1 making one with plywood or cardboard4 ,dials can be painted on the main board4 ,arrows can be attached so they will revolve to give different readings4 ,show how to find the wattage of various types of equipment4 ,show how to figure the cost of the average kwh in a home4 ,for ,further ,information ,your leader can get additional material for you or you may want to have someone from your power supplier talk to your club1 telling about meters1 how they work and how they are regularly checked for accuracy4 ,chart ,one-,,the ,,home ,column ,no4 #a4 #b4 #c4 #d4 ,item ,wattage ,hours ,,kwh per ,cost per ,rating ,used ,month ,month per 7col4 #ax#b7_/ 7,col4 #c x av4 ,remarks ,month #ajjj kwh cost7 ,electric ,iron #aajj #cj #cc 4#hj ,stove #hhj #fj #eb4h #a4ba 7,special rate7 ,,lesson ,,no4 ,b-#h ,credit ,points #c ,,ironing ,,is ,,fun ,,with ,,the ,,modern ,,hand ,,iron ,when you are getting ready to go to school or to a party1 it probably gives you a good feeling to put on a clean1 freshly-ironed skirt1 blouse or dress4 ,but did you ever think about the electric iron that helps so much to give you that well-dressed feeling8 ,when you were younger1 you may have had a play iron and pretended to iron your doll's dresses4 ,now you are old enough to learn about real irons--the different kinds of irons1 how the iron heats1 the kind of cord needed1 the type of outlet necessary1 how to use safety rules when you iron1 and even how to help with the ironing4 ,important ,things to ,know ,there are many different irons1 but the two kinds most important for you to know about now are the regular dry iron and the combination steam-and-dry iron4 ,illustration3 ,the thermostat keeps the iron at an even temperature4 ,it isn't weight alone that makes an iron do its job1 but the heat of the iron4 ,the heat is given off in the sole plate4 ,the automatic iron has what is called a thermostatic control which holds the temperature of the iron at the heat you want4 ,some clothes need to be ironed with a very hot iron1 while others need only to be pressed lightly with a cool iron4 ,the thermostat keeps the iron at an even temperature after you set it for the heat you want4 ,the thermostat is the heart of the iron4 ,take a look at the iron used in your home4 ,it isn't heavy to lift1 and has a handle that fits your hand easily4 ,it looks graceful and has a smooth bottom1 called the sole plate4 ,and it may have a narrow1 pointed tip which is helpful in ironing pleats1 corners and gathers4 ,illustration3 ,your iron has a smooth bottom called the sole plate4 ,the ,iron and ,safety ,if you are going to learn to do some ironing yourself1 the most important thing for you to remember is ,,safety4 ,you should read all about the iron first in the instructions which came with it4 ,never use an iron carelessly4 ,remember the safety rules3 #a4 ,an iron should never be left even for a few minutes without being disconnected4 ,turn off by removing the plug from the outlet1 or by turning the control lever to off4 ,illustration3 ,take hold of the plug--not the cord--when you disconnect it from the outlet4 #b4 ,let the iron cool before putting it away4 #c4 ,wrap the cord carefully around the iron after it is cold4 #d4 ,always stand the iron where it will not fall off on a child or pet or your own toes4 ,,what ,,to ,,do3 ,learn ,about ,your ,iron ,materials ,needed3 ,an automatic iron1 some old play clothes1 towels1 napkins or handkerchiefs1 and an ironing board4 ,steps to ,take3 #a4 ,watch an experienced person iron4 #b4 ,ask questions about what clothes need to be sprinkled4 #c4 ,study the thermostat settings on the dial or indicator4 ,illustration3 ,most irons have a dial to set for the proper heat for different fabrics4 #d4 ,ask about the kind of fabric each piece of clothing is--cotton1 linen1 silk1 nylon1 etc4--and why the iron should be at high heat for some1 cooler for others4 #e4 ,set the thermostat for the amount of heat needed1 and with an older person watching you1 iron some handkerchiefs1 napkins1 bath towels1 and a pair of play shorts or blue jeans4 #f4 ,during a month iron some of these articles for your family1 keeping a record of how many you do and what they were4 #g4 ,take care of your iron4 ,be responsible for storing it4 ---------------------------------------- ------------------------- ,no4 ,store ,iron ,properly ,date ,articles ,ironed ,type of ,article 7check7 ---------------------------------------- ------------------------- ---------------------------------------- ------------------------- ---------------------------------------- ------------------------- ,,ironing ,,is ,,fun #a4 ,i 7use7 7do not use7 an adjustable ironing ,board at home4 ,if ,i do1 ,i adjust it to the height that just clears my knees easily as ,i sit in a comfortable chair4 ,yes ,no #b4 ,there are three kinds of irons usually used--dry iron1 steam iron or a combination steam or dry iron4 ,i use a ---- iron4 #c4 ,i 7have7 7do not have7 the instruction book4 7,if you do1 read about the iron47 ,i know the iron's parts by their correct names4 ,they are----4 #d4 ,i disconnect the iron if ,i leave it even for only a minute4 ,this is a safety measure as fires have been known to start from irons left connected4 ,yes ,no #e4 ,i take hold of the plug--not the cord--when disconnecting the iron4 ,yes ,no #f4 ,i wait until the iron is cold before wrapping the cord around the handle and storing the iron because----4 #g4 ,most irons have a thermostatic control4 ,the iron ,i am using has settings for----4 #h4 ,the purpose of the thermostat is----4 #i4 ,these fabrics need high temperature4---- ,these fabrics need medium temperature4---- ,these fabrics need low temperature4---- #aj4 ,these fabrics need sprinkling4---- #aa4 ,the heat and smoothness of the sole plate smoothes the wrinkles4 ,pushing down on the handle or moving the iron rapidly only makes ironing hard work4 ,i will iron slowly and steadily arranging and moving the garment with the left hand while guiding the iron with the right hand4 7,or the other way for the left handed47 ,yes ,no #ab4 ,i have watched an experienced person iron4 ,yes ,no #ac4 ,i have practiced on handkerchiefs1 napkins and pillow cases4 #ad4 ,here is my record of ironing for one month4 ,month ---- ,your ,name ---- ,date ,i have ironed3 ---------------------------------------- ----------------- ,demonstrations ,you ,can ,give #a4 ,show a dry iron and a steam-and-dry iron4 ,tell the difference between them and when each is to be used4 #b4 ,display garments that look nice because they have been ironed properly1 and those that have been ironed improperly4 ,explain about the heat1 thermostat1 type of iron and why results differ4 ,for ,more ,information ,at a club meeting ask a parent to give a demonstration of ironing different articles4 ,some power suppliers or dealers have people who will demonstrate the proper way to iron1 and how to care for irons4 ,,lesson ,,no4 ,b-#i ,credit ,points #b ,,let',s ,,be ,,friends ,,with ,,electricity ,plan a ,hazard ,hunt ,electricity can be your important lifelong friend and helper1 so you will want to know all you can about it and how to treat it properly4 ,however1 careless and improper use of electricity can do a lot of harm4 ,used properly1 and treated with respect1 electricity can do wonderful things to help you every day in many ways4 ,for safe and proper use of electricity1 all wiring1 fittings1 insulation1 cords and plugs must be in good condition4 ,you can be a detective and track down defects in any such type of electrical equipment that you may be using in your home or on your farm4 ,when you find anything that is wrong1 and know where it is1 and know what to do about it1 you can very likely correct the condition yourself1 such as replacing a worn extension cord with a new one4 ,if you find defects in permanent wiring1 or some places where wires are bare or terminals are needed1 you should tell your parents about them4 ,,safety ,,first1 remember1 should always be on your mind when working with anything electrical4 ,,what ,,to ,,do3 #a4 ,have ,a ,hazard ,hunt ,go on a ,hazard ,hunt to see how many electrical hazards you can find4 ,look for defects such as broken insulation1 worn cords1 splices that are not properly soldered and taped1 loose connections1 or switches that aren't working properly4 ,there are many ways to have a ,hazard ,hunt4 ,choose the method that will be the most fun4 ,use the ,hazard ,hunt ,guide in this outline to check your home1 and other buildings4 ,maybe you'll want to have a friend help check your home1 then you help him check his4 ,or1 why not give each member of your family a ,hazard ,hunt ,guide and have a contest8 ,parents may want to team up against you and other younger members of your family to see which team can find the most electrical hazards in some set time--say #cj minutes4 ,have a ,hazard ,hunt ,committee in your club check all member's homes and buildings and report its findings at the next club meeting4 ,to ,make ,it ,more ,fun #a4 ,put a hazard tag1 like the one shown1 7,figure #a7 by each hazard that is found4 ,leave it until the hazard is corrected4 ,have another contest to see which member of the family corrects the most hazards4 ,illustration3 ,figure #a #b4 ,report on your ,hazard ,hunt at the next club meeting4 ,tell about the ,hazards found1 and what you have done or plan to do about them4 #c4 ,suggest that the entire club have an ,electric ,hazard ,hunt at your club meeting places or any community building4 ,this could be part of one meeting4 #d4 ,have a contest between two teams in the club to see which team can get the most homes in your community checked by the ,hazard ,hunt ,guide4 ,losers could give a party for the winners4 #b4 ,get ,others ,interested ,promote a community ,electric ,hazard ,hunt4 ,enlist the support of power suppliers1 electric supply and equipment dealers1 schools1 newspapers1 radio and television stations4 ,what ,to ,look ,for ,make a complete tour of your home and other buildings and see how many hazards you can locate4 ,when you find a hazard1 put a tag near it to mark it4 ,,safety ,,tips ,put hazard tags near the hazard but not directly on broken or frayed wires1 insulators1 fittings1 or other wiring equipment4 ,do not touch them either4 ,badly-frayed wires should be disconnected immediately from the power supply4 ,in this way1 you will not expose yourself to shock by accidentally touching an exposed live wire that may be carrying current4 #d-;,h ,electric ,hazard ,hunt ,guide ,wiring and ,protective ,devices #a4 ,cable or conduit splices not in boxes---- #b4 ,cable or conduit not securely clamped in boxes---- #c4 ,conduit or armored cable not properly grounded---- #d4 ,cracked or broken insulators 7,figure #b7---- #e4 ,wire not completely covered with insulation---- #f4 ,worn insulation on wire---- ,illustration3 ,figure #b #g4 ,old unused wiring not yet removed---- #h4 ,outlets1 junction and switch boxes not securely fastened and covers not in place---- #i4 ,switches not working properly 7sparks fly as switch is flipped7 7,figure #c7---- #aj4 ,fuses not of proper ampere rating for circuit---- #aa4 ,extension cord used in place of permanent wiring---- #ab4 ,pull chain socket without an insulating link in the chain---- #ac4 ,pull chain socket near plumbing fixtures or where hands may be wet or one may stand in water---- ,illustration3 ,figure #c #ad4 ,no moisture-proof cords for outside weather conditions or heavy rubber cords for motors and motor driven appliances ,lighting #a4 ,fixtures in farm buildings installed so that they might be easily damaged #b4 ,lights in haymows and other dusty locations not protected by dustproof globes #c4 ,outside sockets not waterproof #d4 ,heat lamps not properly supported by non-current carrying wire1 chains1 or brackets 7,figure #d7 #e4 ,light bulbs not frosted1 shaded1 or placed so that light is diffused to prevent glare ,illustration3 ,figure #d ,auxiliary ,wiring #a4 ,outlets overloaded--in other words1 octopus wiring #b4 ,extension cords placed under rugs #c4 ,extension cords run through doorways 7,figure #e7 ,illustration3 ,figure #e #d4 ,extension cords or lamp cords should use underwriters' knot 7,figure #f7 ,illustration3 ,figure #f #e4 ,plug connections fuzzy 7,figure #g7 ,illustration3 ,figure #g #f4 ,extension cords run over heaters or radiators #g4 ,extension cords1 or appliance or lamp cords1 worn or frayed #h4 ,heating appliances without regular asbestos covered wire #i4 ,open sockets or outlets where a baby or small child might stick a finger or metal toy #aj4 ,broken plugs 7,figure #h7---- #aa4 ,loose prongs on appliance or lamps plugs---- ,illustration3 ,figure #h ,how ,many ,hazards ,did ,you ,find8 ,make a chart listing the hazards1 their locations and what you did about them4 ,make your own chart and list what you find4 ,demonstrations ,you ,can ,give ,show and tell others how to have a ,hazard ,hunt4 ,for ,further ,information ,check with your leader1 then ask your power supplier or a local electrician to tell you about safe electrical wiring1 connections and fixtures4 ---------------------------------------- ---------------------- ,hazard ,location ,what ,i ,did ---------------------------------------- ---------------------- ,loose prong on lamp plug,living ,room ,replaced with new plug ---------------------------------------- ---------------------- ,cracked insultor on ,back of house,notified power service wire in house supplier ---------------------------------------- ---------------------- ,conduit not securely ,basement by ,notified parents clamped to box fuse box ---------------------------------------- ---------------------- ,extension cord1 old and ,basement1 by ,replaced with new worn washing rubber-covered one and machine protected it from water ---------------------------------------- ---------------------- ,,lesson ,,no4 ,b-#aj ,credit ,points #c ,,how ,,electric ,,bells ,,work--,,for ,,you ,when was the last time you wanted to get a simple message like ,you're wanted on the telephone1 ,there's someone here to see you1 or ,there's a car in the driveway1 to someone around your place8 ,did you have to walk or run some distance and perhaps shout1 too1 to be heard by the other person8 ,perhaps you had to stop some other work1 or interrupt your favorite kind of fun1 to do this bit of messenger work4 ,if the nature of the message is like one of those mentioned1 and the number of people in hearing is not too great1 then perhaps you can use bells or buzzers or both to do some of your messenger work for you4 ,even though a bell or a buzzer can't talk1 it can convey a message4 ,what to ,do #a4 ,learn how bells and buzzers work1 and learn about the many different kinds4 #b4 ,plan and install a bell system for your home or farm4 ,bells and ,buzzers ,can ,tell a ,lot ,electric bells and buzzers use the same basic principle as the telegraph system1 invented by ,samuel ,morse in #ahdj4 ,although not as important today as it was before radio1 telephone1 and teletype became common1 the telegraph is still in use4 ,bells and buzzers1 however1 are very common and have many uses4 ,they are most often seen in the form of doorbells1 and rare is the new home that does not have one or more4 ,service stations have bell systems to let the operator know that a car is waiting at the gas pumps4 ,a clock signal reminds the homemaker when the cooking time is completed4 ,children are called to and released from school classes by means of bells and buzzers4 ,also1 various alarms employing bells and buzzers warn us when it's time to get up1 or even that the place is on fire1 or that a burglar is trying to break in6 ,let's find out how bells and buzzers work1 what different kinds there are1 the different ways you can control them1 and how you can put them to work for you4 ,you'll find that buzzers and bells can help you with your #d-;,h projects1 and with the proper controls1 can be your eyes and voice in a dozen places at once4 ,why ,they ,buzz or ,ring--,electromagnetism ,if we were to look at an electric bell with the cover off1 we'd find that it would be very much like ,figure #a4 ,a push on the button1 which is just a switch that is normally held open or off by means of a spring1 sends the current from the battery or transformer through the circuit4 ,illustration3 ,figure #a ,you will see that the current passes first through two small coils of wire1 and each coil has at its center a piece of soft iron called the core4 ,when the current is on1 the core becomes magnetized and attracts another piece of iron called the armature with its clapper attached4 ,this action rings the bell1 but it also breaks the current by pulling the spring away from the screw on its return to the power supply4 ,with the power off1 the electromagnet lets the spring return the armature to its normal position1 contact is made again1 and the cycle starts all over again--just as long as you continue to push on the button4 ,buzzers work exactly the same way1 except that they do not have a bell and depend instead on the vibration of the armature for a noise that's not as loud or as musical4 ,gongs or chimes1 that strike only once when the button is pushed1 are made by connecting the armature with the screw by means of a flexible wire4 ,a ,special ,kind of ,electricity ,most buzzers and bells work on a much lower voltage than you normally find in the wires in your house4 ,some are made to work at #f volts1 others at #aj volts1 and still others at slightly higher voltages4 ,you can get these low voltages by using one or more batteries1 or by using a transformer connected to your house current4 ,most bells and buzzers are now powered through transformers4 ,how to ,control ,them ,the push button is the most common means of control4 ,you can use one button to control several bells1 or several buttons to control one bell1 or have several buttons control several bells4 ,because low voltage is used1 adding extra buttons is simple1 inexpensive1 and safe4 ,buzzers and bells can also be controlled by3 clocks1 as in the interval timer on an electric range or in a school class bell system2 temperature detectors1 as in a fire alarm or freezer alarm2 door and window trips1 as in a one-man repair shop or in a burglar alarm2 and treadles1 as in the driveway of a service station4 ,illustration3 ,figure #b ,pick the ,right ,bell or ,buzzer ,some of the many different types of bells1 and various ways of controlling them are suggested in the table below4 ,just remember that no matter what the job or conditions1 you can probably find a bell or buzzer and controls that suit your need4 ,,some ,,typical ,,jobs ,,for ,,bells ,,buzzers ---------------------------------------- ---------------------------- ,number and ,type of location ,number and bell or of bells ,type of location ,job buzzer and buzzers control of controls ---------------------------------------- ----------------------------- ,summon others ,in the house-- ,enough to ,push- ,one at the to the small to cover all buttons telephone telephone medium buzzers usual work and each ,in locations extension outbuildings-- phone medium to large bells ,outdoors-- large weatherproof bell ,all transformer- powered ---------------------------------------- ----------------------------- ,notify club ,medium to large ,one may be ,hose ,one--in member that bell-- enough--if diaphragm the car is at his transformer- mounted on driveway produce stand powered the back of ----------------------- the stand 7,complete driveway including control1 are available1 ready to plug in47 ---------------------------------------- ---------------------------- ,warn of power ,battery-powered ,one near ,relay1 ,one1 at failure to buzzer1 medium the held open main incubator or size poultryman's as long as switch of brooder bedroom power is on1 hatchery closed by or spring if brooder interruption house occurs ---------------------------------------- ---------------------------- ,warn of ,battery-powered ,one1 in or ,temperature ,one1 with dangerously buzzer1 medium near the detector bulb warm size kitchen 7sensitive inside temperature thermostat7 freezer in freezer ---------------------------------------- ----------------------------- ,how to ,plan ,your ,system ,to save your time and steps when the telephone rings for someone else in your family who is some distance away1 you can install a simple bell or buzzer system to summon that person4 ,first1 you must plan what you are going to do4 ,on a large sheet of paper1 draw to scale 7roughly7 a plan of your house and grounds1 including those places where phones are located4 ,it will help if you rule off your paper in #a_/h or #a_/d squares and let each square equal one foot4 ,show the location of poles supporting your wiring4 ,next1 pick out those areas where you or others would likely be when someone else would answer the phone and want to call you to it4 ,after you have thought about this1 and talked it over with members of your family1 show locations on your plan where you think you would like to have buzzers or bells1 and show a button beside each telephone4 7,generally1 you should have a bell or buzzer near each phone1 also47 ,figure #c shows diagrams of various types of systems1 and will help you determine the number of wires you will have to install to connect the buttons and bells that you have planned4 ,inside1 you will connect your transformer and the various buttons and bells with ordinary indoor bell wire4 ,outdoors1 however1 you should use weatherproof #b-wire or #c-wire telephone twist4 ,show on your plan the distances that must be traversed by each type of wire1 and show the number of conductors in each4 ,don't overlook the vertical distances 7one floor to another74 ,illustration3 ,figure #c ,materials ,you'll ,need ,because no two situations are just alike1 it will be necessary for you to make your own list of materials4 ,as a guide1 however1 here is a list of typical materials1 with the quantities left blank1 for you to fill in as your own requirements and measurements dictate4 #aj-volt transformer --- ,door buzzers --- ,doorbells --- ,weatherproof outdoor type bells --- ft4 indoor bell wire --- ft4 #b-wire weatherproof telephone twist --- ft4 #c-wire weatherproof telephone twist --- lbs4 staples 7insulated7 --- entrance insulators 7for attaching weatherproof to buildings and poles7 ,because your transformer must be wired into your regular house current1 you should have some help on this from an electrician or other qualified person4 ,also1 you should get that person to review your plans and materials list before you place an order4 ,install ,according to ,your ,plan ,with the aid of an electrician or other qualified person1 install your transformer1 and test it4 ,you may then go ahead and complete your signal system1 checking carefully with your plan1 and making sure that your installations are both electrically and mechanically secure4 ,test your system in all possible ways that it might be used4 ,demonstrations ,you ,can ,give ,build a demonstration board incorporating a farm or home layout1 with pushbuttons or other controls and bells and buzzers appropriately located4 ,show and tell how the system would save time and energy4 ,show and tell how some of these work1 and their value3 power-off alarm1 freezer alarm1 fire alarm1 driveway alarm4 ,for ,more ,information ,ask your power supplier or your nearest electrical supply house for catalogs or literature on various types of signal systems1 or ask a dealer to show you equipment he has in stock4 ,,lesson ,,no4 ,b-#aa ,credit ,points #b ,,first ,,aid ,,for ,,electrical ,,injuries ,what would you do if you saw someone who had been hurt by electricity8 ,did you know that you could save his life1 if you had taken the time to learn and practice a few simple rules of electrical first aid8 ,first aid training equips you to know what to do and what not to do for the injured until medical help can be obtained4 ,while the main benefits are for you and your family1 no one can call himself a good citizen if he fails to help a stranger who has been hurt4 ,the information given here is only for electrical injuries4 ,perhaps what you learn will inspire you to take a complete course in first aid4 ,what to ,do ,learn how to prevent electrical accidents1 and what to do if an electrical accident occurs4 #a4 ,make an electrical hazard hunt in your home or on your farm4 ,point out to your parents everything that should be repaired or replaced for safety's sake4 #b4 ,read the first aid suggestions that follow4 ,learn them4 #c4 ,get to know the six steps that are outlined for mouth-to-mouth rescue breathing4 ,practice them on your brother1 sister1 or parents4 ,teach the entire family how to do it4 ,electricity ,can ,kill ,in this day of hundreds of uses of electricity1 you should know about electrical dangers4 ,electrocution can occur from either low voltage 7household type7 or high voltage currents4 ,sometimes household voltages are more hazardous because people underestimate the dangers involved4 ,a fraction of an ampere passing through your heart muscles can be fatal4 ,your body offers some resistance to the flow of electricity to ground4 ,if you are standing on wet ground or in water1 or if your skin is damp1 this resistance is greatly reduced4 ,wire cables within walls and cords on appliances are all insulated with a shock proof covering4 ,continued use1 age1 or damage may expose a bare wire and create a hazard4 ,the point of exposure need be only a fraction of an inch4 ,cords are often used and abused4 ,exposed wires and signs of wear are danger signals4 ,always be wary of overhead wires4 ,people have been injured or killed when kite strings1 model plane control lines1 irrigation pipe1 and water well equipment have come in contact with the power supplier's or their own overhead wiring4 ,prevent ,accidents ,underwriters' ,laboratories 7,,ul7 have taken steps to see that minimum safety standards are met in the manufacture of electrical equipment4 ,look for the ,,ul label when you buy cords or appliances4 ,never place cords under carpets or furniture1 or drape them over a nail4 ,replace or repair worn cords without delay4 ,be especially careful when operating electric devices in the bathroom4 ,keep in mind the dangers of a wet floor1 grounded metal pipes1 and wet skin4 ,turning on an ,,ac radio while you are taking a bath is asking for real trouble4 ,there may be shorts in electric devices4 ,keep your hands dry when using them1 and do not touch them along with grounded metal objects4 ,if you ever get a slight shock1 sound the danger signal and do something about it4 ,think1 ,then ,act ,your first thought in rescuing a victim from an electrical accident should be your own safety4 ,speed is also important1 because a few seconds or minutes may save a life4 ,the first question you should ask yourself is ,can ,i quickly turn off the power8 ,this would be easier to do in the home than outside4 ,in the case of a victim trapped in a bathtub from a radio accidentally knocked into the water1 it might mean simply removing the plug from the wall outlet4 ,if a victim is found grasping shorted1 permanently installed equipment and cannot let go1 the main switch might be used for quick release of the current4 ,outdoors1 especially with high tension wires1 your danger in rescue is much greater4 ,to handle the victim1 touch him only with a long dry stick1 dry rope1 or a long length of dry cloth4 ,be sure your hands are dry and that you are standing on a dry board4 ,a broom might be a good lever to pry a victim from a high tension wire but never use a green stick containing sap4 ,first ,aid ,once the rescue has been made and the victim is free of further danger1 check to see if breathing has stopped4 ,if so1 start artificial respiration immediately and send someone for a doctor4 ,artificial respiration must be started as soon as possible after normal breathing ceases4 ,most persons will die within #f minutes or less if breathing stops completely unless they are given artificial respiration4 ,precious minutes may have passed before you get to the victim4 ,since the victim may be within seconds of death by the time you are able to touch his body1 you should seek to obtain an air flow to and from the lungs immediately4 ,the victim may seem stiff as an effect of the current1 so don't give up easily4 ,continue the procedure for several hours4 ,if transportation is necessary1 remember that there may be internal injury1 fractures1 or severe burns4 ,mouth-,to-,mouth ,rescue ,breathing ,there are various effective ways to give artificial respiration1 each with its advantages and disadvantages4 ,the mouth-to-mouth method is recommended as a good one to master4 ,it can be used on victims of drowning1 suffocation1 and asphyxiation1 too4 ,people have been known to save lives with less exposure to the correct procedure than you are getting by reading this4 ,so1 pay attention and remember what you read4 ,step #a4 ,turn the victim on his back4 ,wipe out victim's mouth quickly4 ,turn his head to the side4 ,use your fingers to get rid of mucus1 food1 sand1 and other matter4 ,illustration3 ,head ,position ,step #b4 ,straighten victim's head and tilt back so that chin points up4 ,push or pull his jaw up into jutting out position to keep his tongue from blocking air passage4 ,this position is essential for keeping the air passage open throughout the procedure4 ,illustration3 ,push ,jaw ,up ,illustration3 ,pinch ,nostrils ,step #c4 ,take a deep breath1 place your mouth tightly over victim's mouth1 and pinch nostrils closed to prevent air leakage4 ,for a baby1 cover both nose and mouth tightly with your mouth4 7,breathing through handkerchief or cloth placed over victim's mouth or nose will not greatly affect the exchange of air47 ,illustration3 ,breathe ,step #d4 ,breathe into victim's mouth or nose until you see his chest rise4 7,air may be blown through victim's teeth1 even though they may be clenched47 ,step #e4 ,remove your mouth and listen for the sound of returning air4 ,if there is no air exchange1 recheck jaw and head position4 ,if you still do not get air exchange1 turn victim on side and slap him on back between shoulder blades to dislodge matter that may be in throat4 ,again1 wipe his mouth to remove foreign matter4 ,step #f4 ,repeat breathing1 removing mouth each time to allow air to escape4 ,for an adult1 breathe about #ab times per minute4 ,for a child1 take relatively shallow breaths1 about #bj per minute4 ,continue until victim breathes for himself4 ,what ,did ,you ,learn8 ,true or ,false #a4 ,a broken arm should be splinted before artificial respiration is applied to a victim who is not breathing4 #b4 ,a person who has been severely shocked with an electric current should lie down4 #c4 ,a doctor should be called even though you successfully have revived a victim's breathing4 #d4 ,a fraction of an ampere through the human heart muscles can be fatal4 #e4 ,a copper wire would provide a better path than your body for stray currents1 therefore all appliances should be grounded if possible4 #f4 ,outside wires are never a hazard because they are covered with insulation when they are installed4 #g4 ,cords need not be repaired until you can see bare wires4 #h4 ,tuning in an ,,ac radio while you are bathing is always dangerous1 even though your hands are dry4 #i4 ,in an emergency1 a broom is an acceptable tool for prying a victim off a high tension wire4 #aj4 ,in mouth-to-mouth breathing1 an adult's lungs should be filled #ab times per minute and a child's #bj4 ,demonstrations ,you ,can ,give ,show how to deal with an electrical first aid problem given to you by your leader4 ,for ,more ,information ,ask your leader to have a first aid expert put on a demonstration4 7,many industrial plants and power suppliers have such people47 ,,lesson ,,no4 ,b-#ab ,credit ,points #c ,,how ,,electricity ,,heats ,in ancient times1 people thought that heat was a material just as air is4 ,they called it caloric4 ,when something got warm1 they said1 caloric flowed into it4 ,when something cooled off1 caloric flowed out of it4 ,it did not bother them that they could not see caloric4 ,they could not see air either6 ,now we know that heat is not a material4 ,it does not take up space4 ,it does not weigh anything4 ,instead1 it is a form of energy4 ,and when we say that heat is a form of energy1 we mean that it can be used to do work4 ,what to ,do #a4 ,make a simple resistance heater4 #b4 ,make some popcorn by3 7a7 conduction 7b7 convection 7c7 radiation ,resistance ,makes ,heat ,there are at least four ways that electricity can make heat4 ,the one that we'll cover here is resistance heating4 7,the others are3 dielectric heating1 where the lines of force of an electrostatic field pass through a non-conductive material and heat it2 the heat pump1 which is a refrigerator in reverse2 and electronic heating1 which uses high frequency waves similar to radio waves to create high speed movement of the molecules or tiny particles which rub together to make heat47 ,resistance heating occurs because every conductor of electricity opposes the flow of current through it4 ,some conductors resist more than others4 ,when they do1 a certain amount of warming takes place4 ,the more resistance that is offered1 the more heating there is4 ,some materials1 like silver1 copper1 and aluminum1 offer little resistance4 ,we say they are good conductors4 ,other materials1 like iron1 offer more resistance4 ,they are still conductors1 but not as good as the others mentioned4 ,the size of the conductor1 and its length are the other two things that affect its resistance4 ,the smaller it is1 the greater its resistance4 ,also1 the longer it is1 the greater its resistance4 ,therefore1 when we only want to move electricity from place to place1 we want relatively large1 good conductors4 ,here1 we do not want to make heat4 ,in fact1 we want to avoid it1 because too much heat in the wrong place can cause a fire4 ,but when we want heat1 we choose relatively small1 poor conductors1 and the more heat we want1 the longer they must be4 ,if you will think of the filament inside a lamp bulb2 you may recall that it is a very fine wire1 coiled so as to get a maximum length1 and made of tungsten which has a high resistance4 ,because of all these factors1 this filament glows at a white heat1 and is a source of both light and heat4 ,make a ,simple ,resistance ,heater ,materials you will need3 #a dry cell battery #a foot iron picture wire ,pliers ,use a short strand of iron picture wire and hook the ends to the terminals of a dry cell battery4 ,use pliers so that you do not burn your fingers4 ,disconnect the wires as soon as they become hot4 ,tell why the wires heat4 ,conduction is ,touching ,heat ,conduction occurs when you set a pan containing food right on a heating element4 ,an egg cooking in a hot frying pan is a good example of conduction at work4 ,this method is the most efficient single way of using electric heat for cooking4 ,convection ,depends on ,air ,convection warms food in pans that are not actually touching the heating element4 ,it uses the hot air around the element to carry heat to the pan4 ,your oven in your range works by convection4 ,most houses are warmed in winter in the same way4 ,the heat produced in a furnace warms the air as it circulates through4 ,this air in turn keeps your body warm4 ,radiation is ,like the ,sun ,radiation heating is more difficult to explain4 ,it results when heat or energy waves strike an object and are converted into heat4 ,the energy we receive from the sun is a good example4 ,when you are wearing dark clothes on a chilly day1 you may become uncomfortably hot4 ,the sunshine warms you even though the air around you has not been heated4 ,radiant energy has a way of being absorbed by dark objects and reflected by light colored or shiny surfaces4 ,did you ever notice how snow melts faster on a black top road than it does on a concrete road8 ,the electric heat lamp is one of the most familiar sources of radiant heat4 ,other examples are panels and cables that are built into the walls and ceilings of homes to provide heat4 ,make ,popcorn #c ,ways ,how do you make popcorn8 ,did you know that you can do this kind of a heating job three different ways8 ,materials ,needed ,popcorn ,cooking oil or shortening ,salt and butter #d-qt4 saucepan1 with cover4 7,a glass cover is preferred47 ,potholder ,electric range #b #bej-watt heatlamps #b spring clamp type lampholders ,wire mesh corn popping basket or wire mesh kitchen strainer 7improvise a screen wire cover7 ,first1 make popcorn the way you usually do4 ,set a front surface unit control on the range at medium high4 ,pour enough oil to very lightly cover the bottom of the pan4 ,when the pan is hot1 pour in enough popcorn to cover the bottom with one layer of kernels4 ,use the potholder in one hand to hold the cover on1 and with the other move the pan back and forth across the unit4 ,when the popping stops1 remove from the heat4 ,how did the heat get to the popcorn8 ,second1 make popcorn in the oven4 ,add the oil to the pan1 cover it and put it in the oven4 ,turn the oven on1 with the automatic control set at #djj deg4 ,when the oven indicator light goes off1 this means that the proper temperature has been reached4 ,with the potholder1 remove the pan and add one layer of popcorn kernels4 ,replace the pan in the oven4 ,when the popping stops 7listen for it7 remove the pan4 ,what kind of heating took place here8 ,third1 make popcorn with the heat lamps4 ,clamp the lampholders to the back of a chair or other vertical support4 ,they should be #f to #h inches apart and pointed directly at each other4 ,put about #b tablespoonfuls of popcorn in the ,wire basket or strainer4 ,do not add oil4 ,hold the basket midway between the two lamps4 ,when the popping stops1 turn off the lamps4 ,what kind of heating was this8 ,now1 butter and salt the popcorn you have made and share it with others4 ,what ,did ,you ,learn8 #a4 ,how is heat transferred from one body to another8 #b4 ,could chicks or pigs receive warmth from a heat lamp without the air in the pens becoming warm8 ,explain4 #c4 ,how does a broiler unit in a range cook meat8 #d4 ,how does an oven bake food8 #e4 ,tell why iron picture wire was used instead of copper wire for your heating demonstration4 ,,lesson ,,no4 ,b-#ac ,credit ,points #b ,,mysterious ,,magnetism ,in ancient times1 people found certain rocks that clung together in bunches4 ,these rocks were very mysterious4 ,people didn't understand them and many superstitions grew up about lodestones1 as these rocks were called4 ,lodestone 7sometimes spelled loadstone7 means leading stone4 ,people even told ,columbus not to sail out of sight of land because a giant lodestone was just over the horizon waiting to pull all the nails out of his ships4 ,the ,chinese were the first to use magnets4 ,they found that if you hung a lodestone by a string1 one end of the stone would always point in the direction of the ,north ,star4 ,they had the first magnetic compasses4 ,an artificial magnet can be made by stroking or gently rubbing a piece of steel with a lodestone4 ,this piece of steel then can be used to magnetize another piece of steel4 ,this can be continued on and on4 ,lodestones are not always available but you can get the same results with an electric current4 ,so1 magnetism and electricity are very closely related4 ,what to ,do ,learn about magnetism by doing the experiments that follow4 ,seeing is believing6 ,materials ,you ,will ,need #b dry cell batteries 7#ije7 ,a few feet of ,no4 #ah bell wire #c steel knitting needles or similar hard steel #b ft4 of light thread ,sheet of light cardboard or stiff paper ,permanent magnet 7bar or horseshoe7 ,compass #a or more large nails or spikes ,red and black china-marking pencils or crayons ,iron filings ,wire cutters ,carpet tacks 7,iron filings usually can be found under the grinding wheel in a shop4 ,if you can't find any1 rub some steel wool pads together to produce bits of metal that will do47 ,see a ,magnetic ,field ,cover the permanent magnet with the cardboard or paper4 ,sprinkle iron filings on the paper4 ,tap the paper and note the pattern formed4 ,strings or lines of filings pass from one pole of the magnet to the other4 ,the area covered by the filings is the center of the magnetic field4 ,to remember this1 you might compare the magnetic lines of force that arrange the iron filings to the contour strips in a farmer's field4 ,this magnetic field is one of the important things in our everyday life with electricity4 ,if it were not for the magnetic field1 we would not have electric motors4 ,telephones1 radios1 television1 and many other things we use every day also depend on this magnetic field4 ,illustration3 ,figure #a ,make an ,electro-,magnet ,you can make magnetism work for you by winding several turns of insulated wire around one or more large nails or spikes 7soft iron74 ,connect one end of the wire to the battery4 ,touch the other end of the wire to the other terminal for a few seconds and see how many tacks you can pick up4 ,repeat the experiment using as many turns as possible4 ,how many more tacks were you able to pick up8 ,illustration3 ,figure #b ,you have made what we call an electromagnet4 ,when you disconnect the wire1 the nails fall off4 ,this is one of the advantages of an electromagnet4 ,we can turn magnetism on and off as we wish4 ,picture a crane operator throwing the switch and picking up scrap iron and steel4 ,then he opens the switch to drop the scrap metals4 ,soft iron can be magnetized easily as you have just seen1 but loses its magnetism in a short time4 ,steel is harder to magnetize but holds its magnetism almost indefinitely4 ,make a ,permanent ,magnet ,wrap the insulated bell wire around the steel knitting needle4 ,the wire should be wrapped the full length of the needle4 ,one end of the wire is connected to the battery4 ,the other end of the wire is then touched for just a few seconds to the other terminal4 ,this should make the needle into a permanent bar magnet4 ,if you did not get results1 try two batteries in series1 wind more turns of wire on the needle1 and leave it connected a little longer4 ,do the same thing with the second knitting needle4 ,in the same way1 you can magnetize a screwdriver1 so that you can use it to pick up and hold steel screws4 ,don't do it unless you want your screwdriver to be magnetized4 ,illustration3 ,figure #c ,see ,how ,they ,attract and ,repel ,take one of the magnetized needles and hang it with a thread4 ,a thread stirrup 7,figure #d7 will help keep it level4 ,be sure it is not near other large pieces of steel4 ,watch the needle4 ,does it settle down1 pointing in one direction8 7,check to see if this is the same direction as your compass74 ,if it does1 you have made a compass4 ,the tip of the needle pointing north is called the ,north ,pole 7,north-seeking pole74 ,the other end is called the ,south ,pole4 ,mark the ,north ,pole with a stroke of the red marking pencil4 ,mark the ,south ,pole black4 ,do the same thing with the second needle4 ,you can show this with a sewing needle1 and a notched cork1 and a bowl of water4 ,rest the needle in the notched cork1 and float it on the water4 ,illustration3 ,figure #d ,hold the compass near the ,north ,pole of the needle4 ,what happens8 ,does the ,south ,pole of the needle attract the ,north or ,south ,pole of the compass8 ,try this with the second magnetized needle4 ,see if you can prove the rule that like poles repel 7drive away7 and unlike poles attract4 ,illustration3 ,figure #e ,connect one end of a wire loop to the battery and run the wire directly over the compass4 ,touch the other end of the wire to the battery4 ,which way does the compass point now8 ,if you get some motion out of the compass needle1 this proves there is a magnetic field around the wire when current is flowing4 ,this relation between electricity and magnetism is the thing that makes electric motors and generators work4 ,illustration3 ,figure #f ,make ,many ,from ,one ,lay the third needle 7unmagnetized7 on a table and stroke it with one of the magnetized needles4 7,see diagram7 ,always stroke it in the same direction4 ,raise the magnetized needle at least two inches on each return stroke4 ,thus you can magnetize the needle by using the other needle4 ,illustration3 ,figure #g ,use the wire cutters to cut the first magnetized needle in short lengths4 7,cover the needle with a cloth to keep the pieces from flying47 ,can you show by using the compass that each piece is a complete magnet8 ,hold one end1 then the other1 of each piece to a compass4 ,does each piece have both a ,north ,pole and a ,south ,pole8 ,magnetism and ,animals ,the things you have done show that electricity and magnetism are related in many ways4 ,magnetism is mysterious1 and there are still things to discover about it4 ,it is thought that animals and birds are aided in their sense of direction by magnetism4 ,it is commonly known that when a person gets lost in the woods1 he tends to go around in circles4 ,possibly this is caused by the earth's magnetic field4 ,what ,did ,you ,learn8 #a4 ,where are natural magnets obtained8 #b4 ,how can artificial magnets be made8 #c4 ,what material is needed for a permanent magnet8 ,for a temporary magnet8 #d4 ,how can you find out which is the ,north ,pole of an unmarked magnet8 #e4 ,how many poles does a magnet have8 #f4 ,which magnetic poles attract each other8 #g4 ,why couldn't you make a compass out of a strip of plastic8 #h4 ,what causes the compass to change direction when a wire carrying battery current is held over the needle8 #i4 ,list the materials you would need and tell how you would build a homemade compass4 #aj4 ,tell what you enjoyed most about becoming acquainted with mysterious magnetism4 ,,lesson ,,no4 ,b-#ad ,credit ,points #b ,give your appliances and lights a square meal ,would you say that having enough to eat was pretty important in the home that you know8 ,the food for your appliances and lights is electricity1 and like you they must be fed enough4 ,what to ,do #a4 ,list the appliances and lights in your home4 #b4 ,see if any of them are starving for the electricity they need4 #c4 ,learn how the electricity gets to where it's used4 #d4 ,make a chart of the electrical circuits in your home4 #e4 ,make sure that each circuit is protected with the right fuse or circuit breaker4 ,count ,your ,electrical ,blessings ,many people in much of the rest of the world wish that they could trade places with us1 because we have so many electrical appliances in our homes4 ,of course1 we have not always had as many appliances as there are today4 ,when electricity first came along1 people used it only for lights4 ,then1 they began to add flatirons1 washing machines1 refrigerators1 coffee percolators1 and radios4 ,then more and more electrical things were made for people to use and enjoy4 ,now we have dozens and dozens of uses for electricity in our homes4 ,how many different uses for electricity are there in your home today8 ,ask your parents how many there were when your home was built or first wired4 ,how many were common when your parents began to keep house8 ,some ,homes ,are ,behind ,times ,many older homes were built before electricity was available1 and were wired later4 ,and like them1 some older homes that were wired as they were built had only enough wiring for lights and a few other appliances1 because those were the only uses that were known at that time4 ,but people kept on living in these homes1 and kept adding to the uses they made of electricity without adding to their wiring4 ,what has this meant8 ,well1 if electricity were like cars and trucks1 you could say that some people are trying to put turnpike traffic through a back-country dirt road6 ,watch for ,signs of ,starvation ,of course1 as your state has done with its highways1 some people have expanded and modernized their wiring4 ,but many others have not yet seen this need1 or if they have1 they may have to do it again4 ,here's why3 ,your power supplier delivers current to you at the right voltage or electrical pressure4 ,if the wires in your house are large enough1 they will pass this full voltage on to the appliances4 ,but if your wiring is too small1 the electricity arrives at the appliances so weak that they can't work properly1 and much of what you pay for is wasted4 ,here are some things you can watch for in your own home4 ,they will tell you whether your appliances are getting enough electrical food or not4 #a4 ,a shrinking ,,tv picture--,if it draws in from the sides of the screen1 fades1 loses contrast1 or if the sound becomes distorted1 you may have low voltage4 #b4 ,too much fuse blowing or circuit breaker tripping4 #c4 ,heating appliances are slow to do their jobs4 #d4 ,lights dimming1 when motors or other appliances are turned on4 ,there ,should ,be ,enough ,ways to ,get ,appliance-,food ,around ,if appliances in your home show these starvation signs1 then you may not have enough ways for the electricity to get to where it's used4 ,there are three kinds of these electrical highways or circuits1 and your home should have enough of each3 #a4 ,general purpose circuits--,these serve lights all over the house1 and convenience outlets everywhere except in the kitchen1 laundry1 and dining areas4 ,a rule-of-thumb is3 ,there should be at least one general purpose circuit for each #ejj sq4 ft4 of floor space4 #b4 ,small appliance circuits--,these are not used for lights1 but instead they supply convenience outlets in the kitchen1 laundry1 and dining areas where portable appliances are most used4 ,every home should have at least two small-appliance circuits4 #c4 ,individual or special-purpose circuits--,one of these is needed for each3 electric range1 dishwasher1 water heater1 freezer1 automatic washer1 clothes dryer1 air conditioner1 pump1 and house heating equipment4 ---------------------------------------- - ,actual ,size ---------------------------------------- - ,gauge ,size #ad #ab #aj #h #f ---------------------------------------- - ,fuse or ,breaker #ae #bj #cj #dj #ee ---------------------------------------- - ,max4 ,watts at #aae ,v4 #agbe #bcjj #cdej #dfjj #fcbe ---------------------------------------- - ,max4 ,watts at #bcj ,v4 #cdej #dfjj #fijj #ibjj #abgej ---------------------------------------- - ,illustration3 ,wire sizes commonly used in homes ,each ,circuit ,big ,enough ,the capacity of each circuit is limited by the size of its wires4 ,the chart above shows you the actual sizes of wires commonly used in permanent home wiring1 and what each will carry4 ,notice that each size is given a number1 and the smaller the number1 the bigger the wire4 ,also notice that a given size of wire will carry twice as many watts at #bcj volts as it will at #aae volts4 7,watts are figured by multiplying amps times volts47 ,general purpose circuits usually are either ,number #ad or ,number #ab wire1 at #aae volts4 ,what is the capacity of each1 in watts8 7,number #ab wire is recommended for all new general purpose circuits47 ,small appliance circuits are required to be at least ,number #ab wire4 ,individual circuits are always sized according to the appliance they serve4 ,find the size wire that should be used for a #aj1 #jjj-watt1 #bcj-volt range2 a #aejj-watt1 #aae-volt dishwasher2 a #dejj-watt1 #bcj-volt clothes dryer4 ,only ,one ,fuse ,size ,right ,a fuse in an electrical circuit is like an alert traffic policeman--stopping everything if there's danger4 ,a circuit breaker serves the same purpose1 and the right size is installed when the wiring is done4 ,a policeman uses his brain to tell him when to blow his whistle1 but a fuse depends on the size of the little fusible 7meltable7 metal link that you see under the glass4 ,if too great an electrical load is added to a circuit1 this link will melt and prevent a dangerous overload4 ,if you put in a fuse with too heavy a link1 it will not melt in time1 and the wiring and equipment may be damaged4 ,therefore the right size of fuse is very important1 and is something that you should check in your own home4 ,see the chart above for the right fuse for each size wire4 ,make a ,circuit ,chart ,at one or more places in your home there is a box or panel containing the fuses or breakers for the various circuits4 ,attached to the inside of the door of each such panel should be a chart something like this3 ,illustration ------------------------------------- ,no4 ,description ,fuse size ------------------------------------- #a ,range #dj ------------------------------------- #b ,kitchen ,outlets #bj ------------------------------------- #c ,dining ,room ,outlets #bj ------------------------------------- #d ,living ,room ,outlets #ae ------------------------------------- ------------------------------------- ------------------------------------- ,notice that in our chart we have made columns for a description of what each circuit serves1 its number or position in the panel1 and the proper size fuse for it4 ,because most such charts leave out this last very important bit of information1 you should make a complete new chart1 like the one shown4 ,provide as many lines as there are fuse positions4 ,paste or tape it to the inside of the panel door4 ,then1 ask permission of your parents to disconnect all the circuits by unscrewing the fuses or flipping the circuit breakers4 ,do not touch anything but the fuse rim4 ,then reconnect them1 one at a time1 to find out what each circuit serves4 ,turn on as many lights as you can1 to help you in your detective work4 ,use a test lamp at those outlets that do not have a light connected to them4 ,write two or three words describing each circuit on the proper line on your chart4 ,on a separate sheet1 keep track of the appliances and lights that are on each circuit1 and add up the watts4 7,if the name-plate of any appliance gives amperes1 amps1 or ,a instead of watts1 just remember that amps times volts equals watts47 ,this will tell you if any of them are overloaded4 ,show this sheet to your parents4 ,check the ,wire ,sizes ,disconnect the main switch1 and determine the size of the wires in each circuit4 ,don't include the insulation in your measurement4 ,,be ,,careful6 ,even though you have disconnected the main switch1 the wires coming into it are still live4 ,so1 do not touch any wires4 ,instead hold the wire size chart near them so that you can tell which gauge each one is4 ,write in the proper size fuse for each circuit on your chart4 ,replace ,any ,wrong-,size ,fuses ,do the fuse sizes you have written on your chart agree with the ones that are in place in the panel8 ,get the right size fuses and replace any that are wrong4 ,make sure that you have a reserve supply of the right sizes1 and that they are handy for future use4 ,talk it ,over ,with ,your ,parents ,do you think that your home has enough of the proper size circuits8 ,if not1 talk it over with your parents4 ,they may want to ask an electrician to go over the wiring and make the necessary changes4 ,what ,did ,you ,learn8 7,underline the right answer47 #a4 ,a 7television set1 radio7 is very sensitive to changes in voltage4 #b4 ,dimming lights mean 7static in the wires1 an electrical overload74 #c4 ,wires that become warm from overload make it 7more expensive1 cheaper7 to operate the equipment4 #d4 ,a home of #b1jjj sq4 ft4 should have at least 7three1 four7 general purpose circuits4 #e4 ,one solution to low voltage symptoms is 7heavier fuses1 more circuits74 #f4 ,full capacity for a ,number #ad wire circuit at #aae volts is 7#agbe watts1 #cjjj watts74 #g4 ,a room air conditioner should be on 7a general purpose1 an individual7 circuit4 #h4 ,the purpose of a fuse is to 7let you disconnect the circuit1 automatically prevent overloading the circuit74 #i4 ,the right size fuse is determined by 7wire size1 the store where you buy it74 #aj4 ,a circuit chart should give 7circuit description and fuse size1 the maker's name74 ,demonstrations ,you ,can ,give ,ask your leader to help you plan a demonstration4 ,you can show how lights dim when too many other appliances are connected1 how a fuse protects against overloading1 and the danger of using too large a fuse4 ,for ,more ,information ,ask your ,extension agent1 power supplier1 or electrician for additional help4 ,,lesson ,,no4 ,b-#ae ,credit ,points #d ,,you ,,can ,,measure ,,electricity ,instruments that can detect or measure the flow of electricity have helped to make possible the wonders of electricity as we know them today4 ,scientists in laboratories must have measuring devices for experiments leading to new uses of electricity4 ,power suppliers must have instruments that tell what the generating equipment is doing and to measure the amount of electricity being sold to users4 ,factories need instruments that keep tab on electrical equipment to make sure electricity is being used efficiently4 ,in fact1 almost anywhere you find electric power at work you'll find electrical instruments--even in your home4 ,the one you know best measures the amount of electricity used4 ,another1 in the family car1 shows whether the generator is charging the battery or if the battery is discharging4 ,what to ,do #a4 ,make a simple kind of direct-current meter that will show you that there's a magnetic field around a wire carrying an electric current and that will detect a very tiny current4 #b4 ,make a more refined ,d4,c4 instrument 7galvanoscope7 and measure the voltage of different sizes of dry batteries1 and show how an electric current can be induced4 ,tools and ,materials ,you'll ,need3 ,pair of pliers1 knife1 small hammer #cj feet of ,no4 #bd bell or magnet wire ,compass ,two coins--a penny and a dime ,fine sandpaper ,blotting paper ,plastic or cellophane tape ,wooden blocks 7,see ,figure #d7 ,glue #b small nails ,one #ije dry cell1 a penlight battery1 and two regular flashlight batteries ,table salt ,drinking glass #b paper clips ,two machine bolts ,how ,they ,work ,like many electrical things1 most electrical instruments depend on the action of magnetism created by an electric current4 ,there is a magnetic field or lines of force around any wire carrying an electric current4 ,if this field is controlled and made to react on a sensitive device1 like an easily moved pointer1 we have an electrical instrument4 ,detect a ,magnetic ,field ,first1 let's prove that there is a magnetic field around any wire carrying an electric current4 ,take a piece of wire about two feet long and scrape off about an inch of insulation from each end4 ,connect one end to a battery terminal4 ,make a loop of wire that crosses the face of your compass1 north to south4 ,now touch the other end of the wire to the other battery terminal4 7,,do ,,not attempt to substitute alternating current1 as from a model railroad transformer because its alternating current will cause the compass needle to swing rapidly from one side to the other47 ,illustration3 ,figure #a4 ,put your right hand beneath the wire so that your fingers point the way the needle deflects1 and your thumb will point in the direction that the current is flowing4 ,what happens8 ,your compass needle should move to one side because it is very sensitive to magnetic influences4 ,this proved that the wire created a magnetic field or lines of force when we passed electricity through it4 7,figure #a7 ,detect a ,tiny ,current ,how sensitive is your simple electric meter8 ,take about five feet of wire and wrap it around your compass as in ,figure #b1 keeping the turns bunched together as much as you can4 ,leave about six inches at both ends of the wire extended for leads4 ,scrape the insulation off the last inch of both4 ,rotate the coil and compass until the needle and coil are parallel1 both pointing north and south4 ,illustration3 ,figure #b ,take a copper penny and a dime1 and clean off any corrosion or film on the coin faces with a bit of fine sandpaper4 ,now take a piece of blotting paper about the size of the penny and dip it into strong salt water4 ,place the damp blotting paper between the penny and the dime4 ,place one of your compass coil leads against the dime1 and the other against the penny as shown in ,figure #c4 ,be sure you have good metal-to-metal contact between the wires and the coins4 ,illustration3 ,figure #c ,at the instant that you squeeze the leads against the coins1 watch what is happening to the compass needle4 ,it should move for an instant from the north position each time you press the leads against the two coins4 ,obviously1 the little coin battery you have just made produces a very weak electrical current4 ,even so1 your instrument should be able to detect it4 ,make a ,simple ,galvanoscope ,now let's make a meter that is a little more practical to use4 ,broadly speaking1 a galvanoscope is an instrument that detects the presence of electric currents4 ,it sounds complicated but it is really quite simple4 ,it is named in honor of an ,italian professor named ,galvani who made important early experiments with electricity4 ,a refinement of the galvanoscope is today's galvanometer4 ,other related instruments are the voltmeter and ammeter4 ,these are very important instruments to the electrical engineer4 ,using a glass or anything three to four inches in diameter1 wind about #bj turns of wire in a bunched coil as in ,figure #d4 ,wrap the coil at several points with cellophane or plastic tape to keep it from unwinding4 ,illustration3 ,figure #d ,make a wood base for your coil as shown in ,figure #d4 ,the compass support blocks can be thin wood slats4 ,do not attach them with steel nails or tacks4 ,use glue instead4 ,hold the coil in the slot between the blocks with glue or melted wax or use copper staples4 ,place the compass on the supports and rotate the base so that the compass needle and coil are parallel1 pointing north and south4 ,measure the ,voltage of ,batteries ,do you know what difference the size of dry cell battery makes in the voltage it supplies8 ,your meter can tell you4 ,to test the voltage of batteries we must be able to control our galvanoscope4 ,to do this1 connect a glass of strong salt water in series with the battery as shown in ,figure #e4 ,make sure the wire ends immersed in the salt water are scraped free of enamel4 ,illustration3 ,figure #e ,with one of the batteries connected1 move the wires in the salt water first closer1 then farther apart 7keeping them parallel to each other7 while watching your compass needle4 ,when the needle stays #ae to #bj degrees off north1 lock the wires in the salt solution in place with paper clips4 ,now disconnect the battery you have been using and connect a smaller battery4 ,if both batteries are fresh1 the compass needle should return to almost the same spot4 ,this proves that both batteries regardless of size put out the very same voltage4 ,the larger ones1 however1 are designed to last longer4 ,measure the ,difference between ,series and ,parallel ,using the salt solution as in the previous experiment1 connect two flashlight batteries in series as shown in ,figure #f4 ,the compass needle should move about twice as far as it did with one battery connected4 ,this shows that when you connect batteries this way you double their voltage4 ,illustration3 ,figure #f ,now place your batteries side by side and connect the two top terminals and the two bases as shown in ,figure #g4 ,the compass needle should move only as much as it did for one battery4 ,this is called a parallel connection4 ,you can see that this arrangement does not double the voltage1 even though you used two batteries4 ,illustration3 ,figure #g ,while you have this hookup1 try reversing the position of the leads connected to your batteries4 ,notice that reversing the direction of current flow in the coil causes the compass needle to swing in the opposite direction4 ,test for ,induced ,current ,make a simple coil by winding about #ej turns of wire around a machine bolt core4 ,the bolt should be #a_/d to #a_/b in diameter and about two inches long4 ,connect the coil to your galvanoscope as shown in ,figure #h4 ,pass the coil back and forth close to the end of a permanent magnet4 ,illustration3 ,figure #h ,notice a slight deflection of the compass needle with each pass4 ,you have shown that electricity can be induced in a wire coil by moving it through a magnetic field4 ,currents generated in this way are called induced currents4 ,illustration3 ,figure #i ,now make another coil and core just like the first one and arrange them and a connection as shown in ,figure #i4 ,if you make and break the current to the second coil1 you will build up and collapse a magnetic field around the first coil and again induce a current in it4 ,you will see the compass needle swing back and forth again4 ,these last two experiments give you a crude idea of how an electric generator works1 producing electric current by induction as a coil-wound rotor revolves within a magnetic field4 ,what ,did ,you ,learn8 ,what does every current-carrying wire have around it8 ,how does this help us to measure electricity8 ,how sensitive are electrical instruments8 ,what is the difference in voltage between 7a7 a large and a small dry cell8 7b7 batteries connected in series and in parallel8 7c7 your original connection and the reverse of it8 ,what similarity does the test for induced current show between movement through a magnetic field and the making and breaking of a direct current8 ,demonstrations ,you ,can ,give ,show others how your galvanoscope can detect3 whether a battery is producing current1 which way the current is flowing1 and whether a current is strong or weak4 ,demonstrate how a current can be generated using magnetism4 ,for ,more ,information ,ask your power supplier representative to show you some of the instruments used by his organization1 and to give you a brief explanation of how they work4 ,ask him or an electrician to give you a demonstration of a split-core ammeter4