1 / 14

E l e ct r i c S w i t c h :-

E l e ct r i c S w i t c h :-. E l ec t r i c S w i t ch, a d e v i ce for co m p l e t i ng a n d b r e a k i ng a n e l e c t r i c cu r r e n t , or for ch a n g i ng t he p a t h of a cu r r e n t . E l e c t r i c s w i t c hes a r e a m o n g t he mo s t

michon
Télécharger la présentation

E l e ct r i c S w i t c h :-

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. ElectricSwitch:- ElectricSwitch,adeviceforcompletingandbreakinganelectriccurrent,or forchangingthepathofacurrent.Electricswitchesareamongthemost commontypesofcontroldevicesandareinwideusewhereverelectricityis available. Initssimplestform,aswitchconsistsoftwocontacts,onefixedandone movable.Whenthecontactsarebroughttogether,theswitchandthecircuit areclosedandcurrentflowsthroughthecircuit.Operatingtheswitchto disconnectthecontactsopensthecircuitandstopstheflowofcurrent.This typeofswitch,knownasasingle-poleswitch,iscommonlyusedinthehome forturninglightsonandoff. Three-wayswitchesareoftwodifferenttypes.Inone,currentisdirectedto oneorbothfilamentsofadouble-filament(threeway)lightbulb.Theothertypeisusedinpairstocontrolasinglelightfromtwolocations,suchasthetopandbottomofastaircase. Electricsocket:-socketisfixedonequipmentorabuildingstructureand connectedtoanenergisedelectricalcircuit. Electricalsocketsforsinglephasedomestic,commercialandlightindustrial purposesgenerallyprovideeithertwoorthreeelectricalconnectionstothesupplyconductors. Twopinsocketsnormallyprovideneutralandlineconnections,bothof whichcarrycurrentandaredefinedasliveparts.Neutralisusuallyverynear toearthpotential,usuallybeingearthedeitheratthedistributionboardorat thesubstation.Line(alsoknownasphaseorhot,andcommonly,but technicallyincorrectly,aslive)carriesthefullsupplyvoltagerelativetothe neutral(andtoearth). Threepinsocketsprovide,inaddition,aprotectiveearth[14]connectionfor exposedmetalpartsofanappliance.Ifinternalinsulationshouldfail,ashort-

  2. circuittotheearthedexposedmetalpartswillholdthematalowpotential,circuittotheearthedexposedmetalpartswillholdthematalowpotential, andshouldoperatefusesorcircuitbreakerstoisolatethefaultyappliancefromthesupply. Lampholder:- Lampholdertypes Therearetwotypesoflampholder,plasticandmetal.Theymaybefoundas partofatablelamp,orasapartofapendantlightfitting.Themethodofconnectionissimilarforbothpendanttypeandtablelamp,butthemetalandplastictypesrequiredifferentconsiderations. Thefirstdifferencetonoteisthatplasticfittingshavenoearthconnectionand shouldthereforeonlybeconnectedviaatwocoreflex.Metalfittingsmustalwaysbeconnectedviaaflexwithanearthwire. Metalversusplasticlampholders Thesecondconsiderationisthatmetalfittingsarenotsuitableinsome locations–themostnotableofwhichisbathrooms.Plasticonesmaybeusedinbathrooms,butchoosethetypewithalongerplasticshroudwhichshieldsthecomponentsbetter.Inpractice,metallampholdersaregenerallyonlyusedforcertaintypesoftablelamps. Connectingtheflextoalampholder 1.Switchoffthepowerattheconsumerunitforthecircuitconcerned.Ifyou haveremovablefusesatyourconsumerunit,switchoffthepowerattheconsumerunitandremovethefuseforthiscircuit.Or,inthecaseofatablelamp,switchoffandremovetheplugfromthepowersupply. 2.Unscrewthefittingtoexposetheseparatecomponents.Theconstructionof metalandplasticonesisalittledifferentasyouwillnoticefromthepictures.

  3. 3.Feedthetopcover(andretainingpiecesinthecaseofthemetalfitting)over3.Feedthetopcover(andretainingpiecesinthecaseofthemetalfitting)over theflexandpushthemalongoutoftheway. 4.Notethelengthrequiredfortheconductorstoreachtheirterminals,then stripandpreparetheflex.Moredetailedinformationcanbefoundinour StrippingandPreparingFlexarticle. 5.Usingapairofsidecutters,cutbacktheoutersheathoftheflexaccordingly andtrimofftheexcess. 6.Separatetheconductorsandstriptheinsulationofeachbackbyabout1/2". Twisttogethertheseparatefilamentsofeach. 7.Connectthebrown(live)tooneterminalandsecurewiththeretaining screw.

  4. 8.Connecttheblue(neutral)totheotherterminalandsecurewiththeretaining8.Connecttheblue(neutral)totheotherterminalandsecurewiththeretaining screw. 9.Makesurethatbotharefedroundthesupportswhichpreventstrainonthe connections. Earthformetallampholders 10.Inthecaseofmetalfittingswhich,asnotedearlier,mustbeearthed,you willfindasmallexternallymountedearthterminal.Thisexampleisametallampholderonatablelamp. 11.Thegreenandyellowearthconductorisfedtothisfrominsidethefitting andsecuredwiththeretainingscrew.

  5. Reassemblethelampholder 12.Doublecheckyourconnectionsthenslidethepreviouslythreaded componentsbackdowntheflexandreassemblethefitting,takingcarenottodamageorpullthewiresintheprocess WiringaPlug Preparetheplugandflex 1.Openupthenewplugbyundoingthescrewonitsbasebetweenthe rectangularpins.Insidetherewillbethreeterminals,afuseinaholderandaclampforsecuringtheflex.

  6. 2.Manynewplugshaveatemplateshowingpreciselyhowmuchsheathand conductorinsulationtotrim.Ifyoursdoesn’thavethisyoucanmeasurethelengthsasyougo. 3.Useapairofsidecutterstocuttheoutersheathoftheendoftheflex. 4.Peelthisbackandremovetheexcesswiththesidecutters. 5.Holdthesheathedsectionnexttotheflexclampandseparatethe conductors.Markthelengthrequiredforeachconductor–allowingfortheactualconnection.Cuttheconductorstolength.

  7. 6.Usingapairofwirestrippers,trimtheinsulationofeachconductorbackby6.Usingapairofwirestrippers,trimtheinsulationofeachconductorbackby about5mmorasdetailedonthetemplate. 7.Twisttogethertheindividualfilamentsofeachconductormakingthem easiertoconnect. Connectthewirestotheplug 8.ConnectthebrownconductortotheterminalmarkedLorlive. 9.ConnecttheblueconductortotheterminalmarkedNorneutral.

  8. 10.Ifyouarefittingaplugtoanappliancerequiringanearth,youwillhavea10.Ifyouarefittingaplugtoanappliancerequiringanearth,youwillhavea greenandyellowconductor,whichshouldbeconnectedtotheterminalmarkedwithanearthsymbolorlabelledEarth. Doubleinsulatedappliances 11.Ifyouarefittingaplugtoadoubleinsulatedappliance(labelledwiththe doubleinsulatedsymbol),youshouldnothaveanearthconductorinyourflex. Securingtheflex 12.Fitthesheathedsectionofflexintotheclamp(screwtypeorpushfit).This securestheflexandreducestheriskofthewiresbeingpulledoutoftheirterminals.

  9. Fittingthefuseintheplug 13.Checkwhatratingoffuseisinthecarrier.Mostnewplugsaresupplied with13ampfuses.However,dependingontherecommendedfuseratingforyourappliance,youmayneedtochangethis.Alwaysusethefuserecommendedintheinstructionsordetailedontheappliance.Ifnodetailsaregiven,usea3ampfuseforappliancesupto720Watts,anda13ampforappliancesfrom720Wattsto3000Watts. 14.Doublecheckallyourconnections.Replacethecoverandfastenwiththe retainingscrew. NewLightBulbs-WhytheChange? Weareallawarethatitisnowalmostimpossibleto buytheoldstyleincandescentlightbulbs.Thisis becausethegovernmenthasbannedthesaleofthem andhasinsistedthatalllight-bulbssoldinstoresare thelowenergytype.

  10. Theoldstylebulbswerecompletelyphasedoutatthe beginningofthisyear.ThisputstheUKaheadof othercountriesintheEUwhohaveuntilnextyearto removethesalesofallincandescentbulbs. Therearethreetypesofenergysavingbulbswhich canbepurchased •Compactfluorescentlamps-thesecomeinavariety ofshapesandarethemostcommontypeofbulb •Energysavinghalogenbulbs-Theseuse30%less energythanstandardhalogenbulbs. •LEDs-Goodforuseinplaceofspotlightsandoffergoodlightingatlowenergylevels. Whiletherehasbeensomecontroversyregardingthis change,duetothefactthatlowenergybulbsemita differentsortoflightandtakesomegettingusedto, thebenefitsofthenewrulescannotbe underestimated. Anenergysavingbulbisslightlymoreexpensivetobuy,howevertheyneedtobereplacedlessoftenandwillmakebacksavingsinelectricitybills.Anenergy

  11. savingbulbwilllasttentimesaslongasastandard bulb. •Energysavingbulbsusejustonefifthoftheenergy ofstandardwattagebulb.Sofora60wattbulbyou onlyneedan11wattlowenergyone. Negatives Therehasbeensomeconcernthatlowenergybulbs emitatypeoflightwhichcangivesomepeople headaches.Ifthisisaproblemforyou,pleasetry someoftheothertypesofbulbsavailable.LEDlights maybejustwhatyouarelookingfor. Itisalsotruethatlowenergybulbscontainasmall amountofmercurywhichcanbeharmfulifexposed toskin.Clearlythisisonlyaproblemifthebulb breaks. EnergySavingLamps Theseareusuallycompactfluorescentlampsanduselessenergythan traditionalincandescentlamps.Theyareabletoproducethesameoverallleveloflightingasstandardlampsbut,manypeoplefindthelight

  12. colourtobelessthansatisfactory.Withmanylowenergylamps,they taketimetowarmupandreachfullillumination. FireRatedLighting Arangeoflightfittingsdesignedtomeetbuildingrequirementsinterms offireregulations.Theymayhavecoversandprotectiveelementstosafeguardagainstthespreadoffireandsmoke.Manyfirerateddownlightsincludeasmokehoodmountedoverthefitting.Inloftsandceilingvoids,thepotentialspreadoffirecanbedelayed. FloodlightsandPIRs Theselightsaredesignedtoprovideoutdoorlightingandarecommonly controlledbyPIRdeviceswhichdetectmovementinthevicinity.Thisallowsthefloodlightstocomeononlywhenneededandtoprovideameasureofsecurity.Floodlightsgenerallyprovidealargeamountofilluminationoverawidearea. FluorescentTubes Fluorescenttubesarecommonlyusedinofficesandshops.Although theyareusedinresidentialproperties,thisisusuallylimitedtoutilityareaandgarages.Thelampsuselessenergythanstandard

  13. incandescentlampsbutthelightgivenoffisgenerallynotconsidered pleasing.Theunitsarefrequentlyfittedwithdiffusers. HalogenLamps Halogenlampsarecommonlyusedinlowvoltagedownlighters.They produceasharpcleanlight.Theycanreduceutilitybillsastheyproducemuchmorelightthanastandardlampwiththesamewattage.Theyareknowntolastlongerandhavebecomeverypopularfordomesticlighting. HIDLamps HIDstandsforHighIntensityDischargeandtheselampsgeneratelight byarcingbetweentungstenelectrodes.Thegasinsidethelampfacilitatestheincreasedlightlevelproducedand,comparedtostandardlamps,theygiveoffagreateramountoflightforthesamewattage. IncandescentLamps Incandescentlampsarewhatwewouldallconsidertoberegularlight bulbs.Asanelectricalcurrentpassesthrough,thefilamentisheatedandlightsup.Thereenergyconsumptionishigherthanequivalentlowenergylampsandthelightoutputisrelativelypoorcomparedtootherlampsavailable.

  14. InspectionLights Inspectionlampsarecommonlyusedasworklampswhencarryingout workinpoorlylitareassuchasatticsandunderfloors.Theyareoftenmountedinsideaprotectivecagereducingthechanceofdamage.Theirportabilityenablesthemtobesetupandusedeasilyasandwhenrequired. LED ViewPrices LEDstandsforLightEmittingDiodeandisbecomingmorecommonplaceindomesticsettings.LED lampslastwellandproduceapleasinglight.LEDlightsproducemuchlessheatthanincandescent lampsandaremoreenergyefficient.AdvancedLEDfittingscanproducechangeablelightcolour allowingformoodlighting.

More Related