Electrical Protection & Safety
Ampcontrol’s EFL is an earth fault lockout and frozen contactor protection relay compliant with sections 7 and 9 of AS/NZS2081:2011. While the outlet’s main contactor is open, the EFL will continually monitor the resistance of the phase conductors to earth, on the load side of the contactor. If this resistance falls below an acceptable level, then the EFL will initiate an earth fault lockout trip, preventing the outlet from being started. The EFL will also monitor the state of the outlet’s main contactor and compare it to the state of the auxiliary contactor. If a discrepancy occurs, the EFL will initiate a frozen contactor trip and open the upstream circuit breaker via the CBR contact. It also measures voltage on the load side of the contactor. If voltage is present after the back emf timer has expired, then the EFL will trip the CBR contact on an electrical frozen contactor trip.