ESAB Plasmarc EPP-450 - Digital Meter Calibration Verification; Control Circuit Interface Connectors

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SECTION 6 TROUBLESHOOTING
6.5 Control Circuit Interface Using J1, J4 and J6 Connectors
InterfacetotheEPP-450controlcircuitryismadewithconnectorsJ1,J4andJ6onthefrontpanel.J1has24conductors,J4
has2andJ6has10.
J1-Pand J1-Gprovideaccesstothegalvanicallyisolatedtransistoroutput signalindicatingan“ArcOn”condition.See
Subsection6.8,ArcCurrentDetectorCircuits.J1-LandJ1-JaretheinputsfortheremoteVoltageReferenceSignalthat
commandstheEPP-450outputcurrentSubsection6.9,CurrentControlPot&RemoteVref.J1-RandJ1-Zsupply115VACfor
remotecontrols.SeeSubsection6.6,AuxiliaryMainContactor(K3andK33)&SolidStateContactorCircuitsandSubsection
6.10,PilotArcHi/lo&Cut/markCircuits.
J1-EandJ1-FaretheinputconnectionsfortheEmergencyStopfunction.ForEmergencyStoptooperate,theJumper
betweenTB8-18andTB8-19mustberemoved.
J1-SistheinputtoK8thatparallelsS1switchcontact.When115VACfromJ1-RisfedintoJ1-S,K8activatesplacingthePilot
ArcinHigh.
J4-AandJ4-Barefromanisolatedcontactontheemergencystop(E-stop)switch.Thissignalcanbeusedbytheplasma
controltoindicatethestateoftheE-stopswitchonthepowersource.
Cut/Markselection:ThepowersourcedefaultstoCuttingmodewhenthereisnosignalfedintoJ1-C.When115VACfrom
J1-RisfedintoJ1-C,K11isactivatedplacingtheEPP-450intheMarkingmode.Formoredetailsconcerningtheoperation
ofK11andtheCut/Markmodes,refertoSubsection6.10,High/LowCutCurrentModesandMarkMode.
High/Lowcurrentranges:Thepowersourcedefaultstolowcuttingcurrentrange(35-100A)whennosignalisfedinto
J1-T.Highrange(50Atomaximumcurrentrating)isselectedwhenever115VACisfedintoJ1-TbyconnectingJ1-RtoJ1-T.
J6connectstothewatercooler.J6-AandJ6-Bare115VAChotandneutralrespectively.This115VACactivatesthecontac-
torforthepump.J6-CandJ6-Dconnecttotheowswitch.Theowswitchisclosedwhencoolantisowing.J6-Eand
J6-Hconnecttothecoolantlevelswitch.Theswitchisclosedwhenthecoolantreservoircontainssucientcoolantand
itisopenwhenthereservoirislow.
6.4.4 Procedure For Verifying Calibration Of Digital Meters.
Voltmeter
1. Connectadigitalmeterknowntobecalibratedtothepositiveandnegativeoutputbusbars.
2. Compare the power source voltmeter reading to the calibrated meter reading.  Readings should match within
±0.75%.
Ammeter
1. Externaltothepowersource,connectaprecisionshuntinserieswiththeworklead(s).Thebestshuntisonewitha
valueof100micro-ohms(50mV/500Aor100mV/1000A)andacalibratedtoleranceof0.25%.
2. Useacalibrated4½digitmetertomeasuretheoutputoftheshunt.Theamperageindicatedwiththeexternalshunt
andmetershouldmatchpowersourceammetertowithin0.75%.