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GM8900 Ground Check Monitor

  • Manufacturer: GAI-Tronics | FEMCO (a Hubbell Company)
  • Product Type: Ground Continuity Monitoring

GAI-Tronics | FEMCO

GM8900 Ground Check Monitor


  • Option of Three Different Frequencies
  • Eliminate Monitor Crosstalk
  • Remove Multiple Ground Problems
  • Extended Cable Lengths Are Possible
  • Monitor and Control Over Power Cables


The GAI-Tronics Ground Sentinel® along with the associated filters is designed to monitor the integrity of the ground circuit of power distribution circuits in coal mines. Either the three-phase wires or a pilot wire can be used as a return signal path for the Ground Sentinel. If the ground check circuit has 15 ohms or less loop resistance, the internal relay will be  energized, and the circuit breaker that feeds power to the cable can be energized. A disruption of the ground check circuit that lasts longer than one-fourth of a second will
de-energize the relay and trip the circuit breaker. The time delay prevents false trips. Three LED’s indicate the condition of the ground check circuit. The three-frequency system is intended for the applications on circuits where the ground circuit can’t be isolated by ARC TRAPS or elimination of two ARC TRAPS is desired.