Eaton Digitrip RMS 510 Instruction Leaflet

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

7Instruction Leaflet I. L. 29-885DEffective August 2011Instructions for Digitrip RMS 510 Trip UnitEATON CORPORATION www.eaton.com NOTICEAFTER EACH TRIP OPERATION (WHETHER DUE TO OVERCURRENTPROTECTION OR REMOTE CONTROL) THE AUTOMATIC LOCKOUT-AFTER-TRIP FEATURE OF THE DIGITRIP RMS 510 TRIP UNIT MAINTAINS THECIRCUIT BREAKER IN A "TRIP-FREE" CONDITION, PROVIDED 120 VACCONTROL POWER REMAINS AVAILABLE. THE TRIP UNIT MUST BE RESETBEFORE THE CIRCUIT BREAKER CAN BE CLOSED AGAIN. THE RESET CANBE ACCOMPLISHED EITHER LOCALLY BY PRESSING AND RELEASING THE"TRIP RESET' PUSH BUTTON (SEE FIGURE 2).1.1.3 Discriminator (High Initial Current Release)(For Types LS and LSG Trip Units Only)When the Digitrip RMS 510 Trip Unit is not equipped with anadjustable instantaneous protection setting, i e types LS or LSG, aDlScriminator circuit (or high initial current release) is provided Thenon-adjustable release is pre-set at eleven (11) times the installedrating plug current (In) The DlScriminator is enabled for approximate-ly ten (10) cycles following the initial current flow through the circuitbreaker, provided the load current exceeds approximately 10% of thecircuit breaker frame (or current sensor) rating Whenever the loadcurrent falls below 10% the discriminator is rearmed The release,once rearmed will remain enabled until the load current passingthrough the circuit breaker has exceeded the 10% value for 10cycles The DlScriminator trips the circuit breaker, instantaneouslythe "OVERRIDE / DIS" LED will light "RED "In the event the breaker is not intended to trip out on a circuitwhose current could initially be higher than 11 x In, it is possible tomake the DlScriminator inactiveIf a circuit breaker would close onto a high short-circuit current,when the DlScriminator is inactive, type LS or LSG Trip Units willrely on the short-time delay function before tripping If the faultcurrent exceeds the short-time withstand current capability of thecircuit breaker, the OverRlDe protection function will trip the breakerwithout delay (see Section 1 1 4) Also, please see Section 1 1 5 forother exceptions when Zone lnterlocking is employedThe DlScriminator (high initial current release) can be made inactiveby turning the "OVERRIDE/" setting switch (nearest the bottom edgeof the Trip Unit) from the "DIS" position, to the "[blank]" position (seeFigures 4 and 7)otee:N This switch has eight (8) positions, and seven (7) of the positions show"DIS" in the window, ONLY ONE position shows "[blank]"otee:N When the "OVERRIDE/"window shows "[blank]", the only fast-actinghigh short-circuit protection available is the OVERRIDE (FixedInstantaneous) (see Section 1 1 4 )1.1.4 OVERRIDE (Fixed Instantaneous)Each Digitrip RMS 510 Trip Unit has a Fixed Instantaneous "Override"analog trip circuit pre-set to a value no greater than the short-timewithstand current rating of the circuit breaker in which the Trip Unitis installed Since the specific values vary for different circuit break-er types and ratings, refer to time-current curves, listed in Section 5,for the values applicable to your breaker If the breaker trips due tohigh instantaneous current, the "OVERRIDE/" LED will light "RED"1.1.5 Zone InterlockingZone Selective lnterlocking (or Zone Interlocking) is available (seeFigure 1) for Digitrip RMS Trip Units having Short Delay and/orGround Fault protection Zone Selective lnterlocking provides thefastest possible tripping for faults within the breaker's zone of pro-tection, and yet also provides positive coordination among all break-ers in the system (mains, ties, feeders and downstream breakers) tolimit the outage to the affected part of the system only When Zonelnterlocking is enabled, a fault within the breaker's zone of protectionwill cause the Trip Unit to:• Trip the affected breaker instantaneously, and• Send a signal to upstream RMS Digitrip Trip Units to restrain fromtripping immediately The restraining signal causes the upstreambreakers to follow their set coordination times, so that only theminimum service is disrupted, while the fault is cleared in theshortest time possibleThis signal requires that only a single pair of wires be connectedfrom the interlock output terminals of the downstream breaker'sTrip Unit, to the interlock input terminals of the upstream breaker'sTrip Unit For specific instructions see the applicable connection dia-grams for your breaker listed in Section 5otee:N If a breaker (M) receives a Zone lnterlocking signal from anotherbreaker (F) that is tripping, but the fault current level is less than the settingfor breaker (M), the presence of the Zone lnterlocking signal from the otherbreaker (F) can not cause breaker (M) to trip CAUTIONIF ZONE INTERLOCKING IS NOT TO BE USED (I.E.: STANDARD TIME-DELAY COORDINATION ONLY IS INTENDED), THE ZONE INTERLOCKINGTERMINALS MUST BE CONNECTED WITH JUMPER WIRES, AS SPECIFIEDON THE CONNECTION DIAGRAMS FOR YOUR BREAKER (SEE SECTION5), SO THE TIME DELAY SETTINGS WILL PROVIDE THE INTENDEDCOORDINATION.For examples of how Zone Selective lnterlocking may be used, SeeAppendix A