Electricalsafety
Observethefollowingruleswhenworkingonelectricalequipment.
Important:
Useonlyapprovedtoolsandtestequipment.Somehandtoolshavehandlescoveredwithasoftmaterialthatdoes
notinsulateyouwhenworkingwithliveelectricalcurrents.
Manycustomershave,neartheirequipment,rubberoormatsthatcontainsmallconductiveberstodecrease
electrostaticdischarges.Donotusethistypeofmattoprotectyourselffromelectricalshock.
Findtheroomemergencypower-off(EPO)switch,disconnectingswitch,orelectricaloutlet.Ifanelectrical
accidentoccurs,youcanthenoperatetheswitchorunplugthepowercordquickly.
Donotworkaloneunderhazar dousconditionsornearequipmentthathashazardousvoltages.
Disconnectallpowerbefor e:
Performingamechanicalinspection
Workingnearpowersupplies
Removingorinstallingmainunits
Beforeyoustarttoworkonthemachine,unplugthepowercord.Ifyoucannotunplugit,askthecustomer
topower-offthewallboxthatsuppliespowertothemachine,andtolockthewallboxintheoffposition.
Ifyouneedtoworkonamachinethathasexposedelectricalcircuits,observethefollowingprecautions:
Ensurethatanotherperson,familiarwiththepower-offcontrols,isnearyou.
Attention:Anotherpersonmustbetheretoswitchoffthepower,ifnecessary.
Useonlyonehandwhenworkingwithpowered-onelectricalequipment;keeptheotherhandinyour
pocketorbehindyourback.
Attention:Anelectricalshockcanoccuronlywhenthereisacompletecircuit.Byobservingtheabove
rule,youmaypreventacurrentfrompassingthroughyourbody.
Whenusingtesters,setthecontr olscorrectlyandusetheapprovedprobeleadsandaccessoriesfor
thattester.
Standonsuitablerubbermats(obtainedlocally,ifnecessary)toinsulateyoufromgroundssuchas
metaloorstripsandmachineframes.
Observethespecialsafetyprecautionswhenyouworkwithveryhighvoltages;Instructionsforthese
precautionsareinthesafetysectionsofmaintenanceinformation.Useextremecarewhenmeasuring
highvoltages.
Regularlyinspectandmaintainyourelectricalhandtoolsforsafeoperationalcondition.
Donotusewornorbrokentoolsandtesters.
Neverassumethatpowerhasbeendisconnectedfromacircuit.First,checkthatithasbeenpoweredoff.
Alwayslookcarefullyforpossiblehazardsinyourworkarea.Examplesofthesehazardsaremoistoors,
nongroundedpowerextensioncables,powersur ges,andmissingsafetygrounds.
Donottouchliveelectricalcircuitswiththereectivesurfaceofaplasticdentalmirror.Thesurfaceis
conductive;suchtouchingcancausepersonalinjuryandmachinedamage.
Donotservicethefollowingpartswiththepoweronwhentheyareremovedfromtheirnormaloperating
placesinamachine:
Powersupplyunits
Pumps
Blowersandfans
Motorgenerators
Similarunitstolist edabove
Thispracticeensurescorrectgroundingoftheunits.
Ifanelectricalaccidentoccurs:
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