Show The Automobile Simplified By FREDERICK C. C GUERRLICH bi E. E Electrical Terms A few tew days ago ao a capable chauffeur made the writer r realize Uz that thai even en experienced experienced experienced mechanics are aro often ofton unable to understand understand understand un un- the explanations of or the electrical system of or the auto as given ghen In th the Instruction in instruction instruction In- In books because they do not cl clearly arly understand tho the meaning of or the various terms used and the tho purpose of ot tho the simple and used much-used electrical de devices do- do vices An explanation of these simple terms and devices as used on the auto will therefore probably help many The Volt Tho The olt volt Is hi tho the unit of at measure of oC the electric pressure which causes the Uie current current current cur cur- rent to flow low through the tho wires and electrical devices It corresponds to tho pound Thus if It water Is to bo be made to flow through a pipe up to the top of at a II ahouse ahouse house etc there must bo be a pressure at atthe atthe atthe the source possibly furnished b by a pump In order to make it it do so Wo Ito o would oula say eay that the pressure of or the water would be bo so many pounds pound In the same came way it t requires a pressure at the source the 1 generator battery or magneto to maJ make electrical current flow through wires lamps lamp coils colle etc ete and we Yc call this electrical elec elec- trl al pressure so EO many volts High voltage and high tension or low voltage and low tension moans moan the same thing thing- namely high electrical or low lo electrical pressure The Tho Ampere Tho ampere Is the unit of measure of I the thc rate of or flow now or in Other words the tho quantity of or electricity flowing through a given time Thus If It water were flowing through h a pipe and you put a a. meter In Into Into into to eee see how much flowed past a c certain point In a 1 minute you ou would say that so many gallons were flowing past per minute min rain ute In the same way If It you ou put an nn ammeter ammeter am nm- meter an abbreviation for tor amp meter r-m r r-mettr r t r I In tn an electrical circuit you would find the quantity of ot current flowing through It in ina ina I I a given time and any tay y there were EO so many amperes flowing Tho The time need not be bo i I specified however as with water Tho The i Instruments used to measure the amperes automatically take care cue of or this It Is not I necessary to say ay IllY amperes per minute etc The Hour Ampere Hour The hour ampere Is a term used to de deI denote denote de- de I I note the tho alz site of a storage battery batter It being be being bethe be- be ing the number of amperes which will flow from a a. fully charged battery multiplied multiplied multiplied multi multi- plied by bytho bythe the number of ot hours the they will flow before the battery is completely discharged dis dis- charged Thus a Il hour forty battery battery battery bat bat- tery will yield tort forty amperes for one hour 1 I or one ampere for tor forty hours houn or four amperes for tor ten hours or eighty eight for half an dour hour etc dc I Resistance A resistance Is 18 a device generally a con coil or band of ot German Gorman silver GUver which Is placed In tho the Circuit between tho the b battery or generator generator generator gen gen- gen gen- and some of ot the units In order to cut down the amount of ot current which can flow v to th them m. m or to cut down the tho voltage In looking for a a. comparison In Inthe Inthe the tho flow of ot water I think of a alve valve or faucet rL If It you open a a. faucet wide the water water wa ona wa- wa ter will flow out In a hOA heavy vy stream and andou jou OU will have ha to firmly grip the glass held under It or It will b be driven from your hand and while when tho the faucet Is partly I closed a resistance Is offered to the flow of tho the water and only a thin stream will flow out and it will have practically no force torce In many headlights when the tho lights are arc burning bright tho the current can cango cango cango I go directly from tho the battery to tho the bulbs I I vH H rD rDe J I R Ro L o e e. e l r t e. Battet F CT 1 I f r a I fo t F c 2 J r r I t I 1 11 I 7 Y r t FI Flo without cluck check but when the switch is thrown to dim the current must first pass PIlS through a resistance BO so that but buta a small smitH amount of It ft can get to tho the bulbs and they will give gl out but a dim light Thus In the tho drawing awing Fig 1 when the headlight button H Is la pulled out there will be a practically unobstructed flow tIow of the current from tho the battery to the tho lights When WIlen the tho dimmer button D CUD is pulled out and CH H pressed In tho the current current cur cur- curI rent will have I to pass paea through tho the re resistance re- re R n R and ond the current C flow will be obstructed by this resistance and tho the lights be dim 1 Ground As the metal of the engine frame transmission etc etc Is a good conductor of ofel el electricity it Jl can often otten bo be us used forthe for forthe forthe the return of or ortho tho the curr current nt Instead of ot using a a. wire for tor this purpose 8 and EO so man many wires can be eliminated When hen the current returns through the metal In this It tt Is said to go through tho the ground wile while the tho wire att attached ched to the engine transmission etc Is said laid to be grounded This does not mean moan that tho current actually goes Into the earth or ground Telephone and find telegraph companies companies com com- however do actually use th the ground for th the return of ot the current and the expression Is i borrowed from them Short Circuit Th The current currant in order to do the work re required required re- re of It must pass from tho the battery batter through certain units unit as ns a a. switch coil coll colland and Int Interrupter and then back to the bat bat- tery If It anywhere In tho the circuit or be between between be- be tween apy of or the units there thore Is a bare wire Ire In contact contA t with the m metal moui tal of or the engIne engine en en- gine so tiO that the current can cnn get back to the he battery b before It ore oro hat has gone through all of or the tho required Med cd units the entire aye tem tern will be inoperative the current current current cur cur- rent to so finds a sort short cut back to the bath bat bat- tery h we e say ay that It Is short circuited or that there la Is s a a. short Probably more trouble with the electrical elec elec- system m la is duo to short circuits than to anything else ehlo They may be caused b by a worn or oll soaked oil d wire to detects defects In tho the units themselves but the writer b believes that they art are the most often otten found at the ends enda of the tho wires and binding bind bind- ing Ing- posts I The he ends or terminals of or the wires aro are necessarily baro barn and often orten they are arc so 80 bent or attached to th these theao binding posts posts no so that a small portion comes In contact with tho the metal meld of the Instrument Or engine A drop P of or water r due duo pos pos- possibly il aI sibly Jy dy to the condensation of the tho moisture Cult In tho he air 41 will often orten cause a short cir cult especial y in the B secondary con or high tension s Series and Parallel There are Bro two ways way In which the lamp lamps c cells IB of or a battery and units In an t el electrical elec elec- c. c system can b be connected namely In series and aud In parallel When hen the units lamps etc nr are so 80 connected that th tM the curr current h rust must papa pEta through them one after the other they thet are said to b be In series Fig o 2 shows shown how lamps lampa arc aro connected connected con con- d In 6 serIes while Fig 3 shows shows a Do set act of dry cells so connected A failure fall fail UTe ure of or one unit In a a. system connected In will win cause causo a failure failure of or the whole If U on t po of th the I ll light t of f Fig 2 r were to burn burnout burnout burnout out the other ether light light would also aleo co o out When each fl light or other unit unit has ll rte Its c separate ar e circuit so 10 that the current does doe not pass through one after tho the other as In ill the tho series they are said to be con COn- connected faded neele In p parallel Fig Tig 4 shows lamps rl In Tn I Ph P h 1 tf I f lIht ht were to go out It would not nol affect the tha theother theother other Fuse When an electric current passes through h ha a wire lamp filament or other device it Jl will wll cause tn the wire etc to become hot AH As th the greater grealer the Hie amount of ot current the l hotter the Ire becomes It often otten happens hap pens t that at fl parts become oo so hot ab as to burnout burn burst out To prevent this a a. fuse tUM which willburn will willburn willburn burn out at an lower than the device it In is supposed d to protect I In is placed I In series Merles with the tho device device By burning out It l breaks or opens the tho circuit before harm barm can be bo done It la is a safety safely device nr v. of nf PT |