Eaton Cutler-Hammer Digitrip RMS 510 Instructions Manual

Also see for Cutler-Hammer Digitrip RMS 510: Instructional Leaflet Instructions Instruction leaflet

AD 33-855-4 Page 51SECTION 1O DIGITRIP RMS RETROFITSWITCHGEAR ASSEMBLYAPPLICATIONS1O.1 Zone lnterlockingZone Selective lnterlocking (ZSl) capabilities areavailable with Digitrip RMS 510, 610, 810, & 910Trip Units. ZSI provides positive system coordina-tion by allowing the Breaker closest to the fault totrip without any preset time delay. This is achievedby setting up the distribution system as shown inthe adjacent diagram. The hard wired connectionbetween Trip Units sends a restraining signalupstream, allowing the Breaker closest to the faultto trip instantaneously.ZSI's superior system coordination ensures thatthe Breaker closest to the fault will trip withoutpreset time delays while reducing stress on thedistribution system.10.1.1 Zone Selective lnterlockingFig. 10-1 Zone Selective InterlockingFault 1 - There are no interlocking signals.The main Breaker Trip Unit will initiate the tripinstantaneously.Fault 2 - The feeder Breaker Trip Unit will initiatethe trip instantaneously to clear the fault; and Zone2 will send an interlocking signal to the Zone 1 TripUnit. The Zone 1 Trip Unit will begin to time outand, in ihe event that the feeder Breaker in Zone 2would not clear the fault. the main Breaker in Zone'1 will clear the fault in 0.5 seconds.Fault 3 - The branch Breaker Trip Unit will initiatethe trip instantaneously to clear the fault; Zone 3will send an interlocking signal to the Zone 2 TripUnit; and Zone 2 will send an interlocking signal toZone 1 .Zone 1 and Zone 2 Trip Units will begin to time outand, in the event that the branch breaker in Zone 3would not clear the fault, the feeder breaker inZone 2 will clear the fault in 0.3 seconds. Similarly,in the event that the feeder breaker in Zone 2would not clear the fault, the main breaker in Zone1 will clear the fault in 0.5 seconds.NOTE: Digitrip RMS Zone lnterlocking will trip theBreaker instantaneously on Short Time (S)or Ground Fault (G) Delay Trip Functionsunless it is defeated as described in thefollowing text.For RMS 510 Basic Retrofit Kits, Zone lnterlockfunctions are not wired out from the Trip Unit.The External Harness provided consists of a smalljumper plug that shods out the Zone lnterlocksignals at the Trip Unit.For RMS 510 Zone, 610, 810, & 910 Retrofit Kits,Zone lnterlock functions are available at the CellHarness assembly as shown in Figure 12-12.TheBreaker External Harness plugs into the CellHarness Assembly, which includes provisions forexternal wiring connections as shown in Figure12-12. Shorting jumpers are provided at the Termi-nal Block Assembly to defeat the Zone lnterlockfunctions. These jumpers can be removed andselective Zone lnterlocking schemes applied.Typical connection schemes for multiple CircuitBreakers are shown in Figures 10-2 and 10-3.i 5OOA P1CKUPi 0.3 sEcoNDs rME DELAYi.-2qNs sg1s611ygi INTERLOCK WIRINGBREAKER NUMBER 1GROUND FAULT SETTING:l2OOA PICKUP0.5 SECONDS TII\IE DELAYBREAKER NUMBER 2GROUND FAULT SETTING:i BREAKER NUMBEB 3--J GROUND FAULT SETTING:3OOA PICKUPNO TIME DELAYEtfective 9/01 FlT.il