AMR’s GM-300 Ground Check system is intended for use on all high voltage systems where a pilotwire is available. Gound Check systems using the GM-300 are suitable for applications on power systems up to 25kV AC including low and medium voltages.  For power systems over 25kV, contact AMR for recommendations.

  • MSHA approval #041890AMR
  • Test Switch included
  • Versatile sensitivity adjustment
  • Longlife LED indicator lights
  • Low and high resistance indications
  • Simple troubleshooting
  • Reduced nuisance trips
  • Field replacement boards
  • Plug-in relay
  • Optional mechanical trip indicator
  • Operating window width of 3 ohms
Dimensions: 7″W x 9.5″H x 6″D
(177.8mm x 241.3 x 152.4)
Enclosure Rating: NEMA 4X, Powder Coated Aluminum
Weight: 6 lbs (2.7kg)
Installation: Front Instrument Panel Mount
Operating Voltage: 120 VAC
Current Consumption: 750 mA
Operating Temperature: -20 to 70C
Humidity: 0 to 90% R.H.
Phase Voltage Filters: 7.2 kV, 15 kV, or 25 kV
Sensitivity: 3 ohms
Trip Resistance: +/-1.5 ohms
Trip Delay: No
Pilot Voltage: 12 VDC
Outputs: (1) Normally open or Normally Closed Contact Relay-250VAC @ 10 A
Display: LED indicators
Backup Battery: OPTIONAL-Rechargeable 12VDC, 12 Ahr
Test Feature: Yes
Option: Blocking Inductor-prevents parallel earth pass of signal
Warranty: 90 Days