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Protection Relays
Auxiliary Relays

Home > Grid Automation > Protection Relays > Auxiliary Relays > MCAA

Auxiliary Relays

The MCAA relays are current operated attracted armature units of compact design with a positive action and a high degree of mechanical stability. The MCAA is used for connecting in series with tripping relays or circuit breaker trip coils to monitor the presence of current on an ‘all or nothing’ basis. MCAA relays provide output contacts and operation indicator for circuit breaker control, remote and local alarms and event recording.

Models Available

There are three versions of the MCAA relay, each with a different type of contact reset mechanism. MCAA relays are DC current operated (AC versions are available on request). An optional hand reset operation indicator is available.

Supply for the following models remain available:

  • 11 Single element with self reset contacts
  • 12 Single element relay with a combination of self and hand reset contacts
  • 21 Double element with self reset contacts

GE has discontinued manufacturing for the following models: