Eaton ATC-900 Operation And Maintenance Manual

Also see for ATC-900: Instruction booklet Operation and maintenance manual Manual Instruction booklet Operation and maintenance manual

IB140012EN For more information visit: www.eaton.comInstructional BookletEffective: March 2021 Page 39Operation and Maintenance Manual,Automatic Transfer Switch Controller, ATC-900-Immediately turn on Preferred Source Gen Start-Start Emergency Source TDES counting downPreferredAvailable?EmergencyTDES=0?-Turn on Emergency Source GenStartYesNo NoEmergencyAvailable?-Set transfer switch to Preferred Source (No TDN or TDEN ifswitch was previously on Emergency Source)-Cancel Emergency Source TDES-Set Emergency Source to Idle StateYesPreferredAvailable?-Set transfer switch to Preferred Source (No TDN or TDEN ifswitch was previously on Emergency Source)-Turn off Emergency Source Gen Start-Set Emergency Source to Idle stateYesNo No-Set transfer switch to Emergency Source (No TDN or TDNE ifswitch was previously on Normal Source)-No Change to Preferred Source Gen Start or state.YesSecondary-InActive?-Turn off Preferred and Emergency Source GenStarts-Set Preferred and Emergency Sources to Idlestate-Follow normal procedures to transfer betweenPrimary and Emergency sources based on sourceavailability, etc.Wait for nextSecondary-In ActiveSecondary-In goesActiveYesNoSecondary Controller with Preferred SourceDuring startup, if Emergency source comes up first, followed quickly byPreferred source, the load will be initially powered by the Emergencysource followed by a transfer from Emergency to Preferred source withnormal TDEN/TDN delays. Use manual retransfer to avoid this if desired.TDEC will be used to “cool down” Emergency generator.