GM-250
The GM-250 is the most advanced high voltage ground monitor on the market, available in both pilotless and pilot wire operation. Offering a 45 ohm trip resistance, 250 ms time delay for reduced nuisance tripping, and immunity to DC and AC stray currents. Easy installation and maintenance and approved to work with cable lengths to 10,000 feet, the GM-250 saves cable costs and repairs.
- Pilotless or pilot wire operation.
- Continuity monitor (45 ohm trip resistance)
- Time delay (250 mS). Reduces nuisance tripping.
- Immune to high and low voltage conditions. (+10%, -30%)
- Immune to DC and AC stray currents.
- Easy installation and maintenance.
- Transient protection on all inputs and outputs.
- Approved to work with cable lengths to 10,000 feet.
- Saves cable cost and repairs.
- Only MSHA – accepted high-voltage pilotless ground monitor.
| Dimensions: | 6″W x 7.75″H x 8.5″D (152.4mm x 196.9 x 215.9) |
| Weight: | 11.25 lbs (5.1 kg) |
| Certifications: | MSHA |
| Enclosure Rating: | Industrial Powder Coated Aluminum |
| Main Assembly Installation: | Flush or Flange Mount |
| Operating Voltage: | 120 VAC |
| Current Consumption: | 250 mA |
| Operating Temperature: | -20 to 70C |
| Humidity: | 0 to 90% R.H. |
| Phase Voltage Filters: | 7.2 kV, 15 kV, or 25 kV |
| Trip Resistance: | Adjustable up to 75 ohms |
| Trip Delay: | 250 ms |
| Reset Mode: | Auto |
| Transmitter Frequency: | 1000 Hz +/- 1% |
| Transmitter Output Current: | 200 mA |
| Outputs: | (1) Normally open or Normally Closed Contact Relay |
| Contact Relay Rating: | Form C – 120 VAC @ 10 A or 240 VAC @ 5 A |
| Contact Operating Mode: | Fail Safe |
| Display: | LED indicators, Analog Current Meter |
| Backup Battery: | No |
| Test Feature: | Yes |
| Option: | Blocking Inductor-prevents parallel earth pass of signal |
| Warranty: | 90 Days |
- GM-250 Datasheet – English (PDF)
- GM-250 Datasheet – Spanish (PDF)
- Ground Monitors Brochure (PDF)