Starting at $999.00

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  • 2-, 3-, & 4-wire testing
  • 0 to 300V AC earth voltage
  • Store & recall up to 200 test results
  • Autoranging, test hold, data hold, & auto power off
  • Automatic I (current) & P (potential) spike checks
  • CE & CAT IV 300V approvals
  • 1 Year warranty

What's in the Box

  • Built-in hard carry case
  • Alligator clip test leads
  • 4 auxiliary earth bars
  • 8 AA batteries

The Extech GRT350 Ground Resistance Tester is used to ensure good ground system installation. Use the GRT350 to check the resistance of the ground as well as the soil resistivity before you install your ground rods. This tester includes all hardware necessary to measure Earth Ground Resistance in 3 ranges, from 20 to 2000Ω, and Resistivity from 0.06 to 628kΩm.

Electricians and technicians should also check their ground system periodically for predictive maintenance ensuring the resistance level doesn't exceed the allowed safety level.

The GRT350 has a CATIV 300V safety rating. That means it's designed for use with devices connected to raw voltage distribution lines and/or located outside (Pole Transformers, Service Drops, Overhead/Underground lines etc.). Maximum voltage rating of these devices shouldn't exceed 300V.