AEMC 2117.61 - Clamp-on Ground Resistance Tester Model 3731

The Clamp-on Ground Resistance Tester Model 3731 measures ground rod and small grid resistance through any season, without the use of auxiliary ground rods.

Clamp-on Ground Resistance Testers are used in multi-grounded systems without disconnecting the ground under test. The Model 3731 simply clamps around the ground conductor or rod and measures the resistance to the ground. By performing measurements on intact ground systems, the user also verifies the quality of the grounding connections and bonds. Resistance and continuity of grounding loops around pads and buildings may also be measured. The Model 3731 also provides alarm and memory functions.

Both models include a current measurement function. The probe’s high sensitivity enables measurement of leakage current flowing to the ground or circulating in the ground loops down to 1mA and neutral and phase currents to 30Arms. This feature provides additional information which is vital in distribution ground networks carrying higher levels of noise and harmonics that affect power quality.

The Model 3731 offers an alarm function and a memory (logging) function. In the alarm mode, the probe will audibly and visually indicate readings beyond setpoint. The user may also have the alarm initiated above or below the set point. This alarm feature permits quick field checks where only “pass” or “fail” readings will suffice.

Applications

• Measure electrical ground rod and grid resistance
• Use on multi-grounded systems without disconnecting the ground rod under test
• Measure resistance and continuity of grounding loops around pads and buildings
• Measure leakage current flowing to the ground or circulating in the ground systems
• Conduct field surveys and retrieve and analyze readings at a later time
• Use on cell towers and telecommunication sites
• Use on pools, spas, and other consumer installations