M-0188A Syncrocloser® Check Relay

Please Note: As of 12/31/2022, Beckwith Electric will no longer be manufacturing the M-0188A Syncrocloser Check Relay.

  • Beckwith will accept orders for these products until 8/31/2022 and all products ordered must ship before 12/31/2022.
  • Please contact us to request a quote and place orders.
  • This product may have an alternative replacement product, M-3410A or M-3425A, depending on your application needs. Please contact us for details.


The M-0188A Syncrocloser Check Relay is used as a permissive relay for secure reclosing of a circuit breaker by verifying that voltage and phase angle conditions are within pre-set limits before allowing the breaker to close. Adjustable front panel controls are provided for upper and lower voltage limits, voltage difference (ΔV) limit, phase angle limit, time delay and dead line/bus limits. Analog outputs of phase angle, voltage and ΔV are provided for SCADA system interface. Phase angle, voltage and time delay dial settings are independent and do not vary with input conditions.

  • Accurate, independent controls require no additional instrumentation for field setting.
  • Voltage limit ranges and dead line/dead bus closing features are optional.
  • Remote contacts to shift phase angle or time setpoints are standard.
  • Transducer analog outputs are SCADA compatible.