Application
The relay type NM20 can be used for protection of large size motors in MV systems.
For any grounded systems (solidly grounded, ungrounded or Petersen coil and/or resistance grounded) the protection can be used on feeders of any lenght.

Protective functions 26 - Thermal probes 27 - Undervoltage 27V1 - Positive-sequence undervoltage 27V2 - Negative-sequence undervoltage 37 - Undercurrent 46 - Negative-sequence overcurrent 49 - Thermal image 50 - Phase overcurrent 51LR - Locked rotor 50N/51N - Residual overcurrent 59N - Residual overvoltage 66 - Restart inhibit 67N - Directional ground fault BF - Circuit breaker failure