The Three-Terminal Ground Resistance Tester is the economical choice for electrical contractors, plant electricians, telephone and CATV technicians making routine ground resistance tests on single electrodes and other simple grounding systems. The instrument is easy to use for quick measurement of resistances from 0.5 to 500 ohms.

Because factors such as seasonal variations in temperature, moisture and salt content affect soil resistivity, periodic tests are essential to ensure that resistance to ground remains at a safe value.

The instrument is simple to operate:

• Drive probes and hook up the leads.
• Push switch to READ and ground resistance is displayed directly.
• If reading is questionable, switch to CHECK to verify test lead continuity and probe resistance.

Designed for simplicity of use, the instrument is operated by a single three-position switch to read the measurement, check the probe resistance and turn the instrument off. Measurements are displayed directly in ohms; range changing, multipliers or calibration adjustments are not necessary.