Siemens RAJA+ 3TE7421 - Maintenance Procedures; General Maintenance and Component Replacement

3
Maintenance:
• SwitchoffthestarterandPutLatchontheOFFpush
button,(marked‘O’).Disconnect the main supply by
switching the main switch & Rocker Switch Off before
doing any maintenance.
• Keeptheinteriordustfree.
• Re-tightentheterminalscrewsfromtimetotimeasper
speciedtorqueintable2.
• Nomaintenanceisneededforoverloadrelay.Pleasedo
notopentherelay.
• Replacecontactsofthecontactoriftheywereseverely
pittedorwhenonly40%oftheoriginalcontacttips
remains.
• ReplacementofContactorOrIndividualmounted
OverloadRelay(ReferFig.4):
1. Slightlyloosentheoutgoingterminalscrewsofthe
relay.
2. Disconnectthewiresconnectedtotherelay
terminals.
3. Slightlyloosentheoutgoingterminalscrewsof
thelinecontactor(Forcontactormountedrelay)/
adaptorplate(Forindividualmountedrelay).
Fig. 4: Contactor -Relay Connection Replacement of coil
Fig. 5: Adaptor plate for Individual mounting of Bi-relays
3US50/52/55/56:3US9150/3US9152/3US9155/3US9156
3US50 3US9150
3US52 3US9152
3US55 3US9155
3US56’ 3US9156
3US58 3US9158
Fig. 6: Adaptor plate for Individual mounting of Bi-relays
3US58:3US9158
Note:No.2(3Nos.)andNo.4(2Nos.)suppliedlooseinaplasticbag
Contactor
outgoingterminals
Hookonrelayfor
engagement
4. FollowinstructionsgiveninFig.4(Forcontactor
mountedrelay)/Fig.5,6(Forindividualmounted
relay)forremovalofrelay.
5. Selectaproperrelayexactlyaspertheoriginal.
6. Connecttherelayterminals(L1,L2,L3)to(T1,T2,
T3)ofQ1linecontactor(Forcontactormounted
relay)/adaptor(Forindividualmountedrelay).
7. ConnecttherelayterminalstoTerminalblockTB2.
 Care should be taken to x the relay terminals &
relay to contactor / adaptor in the exact position
shown in Fig. 4, 5, 6.
8. Ensurethatrelayhookisengagedinthesloton
contactororadaptor.
9. Tightenthecontactor/adaptorterminalscrews.
10.Re-connectthedisconnectedwiresandcheck
connectionsbyreferringtothewiringdiagram.
FormoreTechnicaldetailslikeLMR-Awiring,operating
sequence,mountingdetailsetc.,referInstallation&
Troubleshootingguideno.A5E50797230A.
3US58
3US58
3US9158