This document is the user guide for the Extech GRT300, a microprocessor-controlled 4 Wire Earth Resistance Tester. The device features an auto-ranging capability with four ranges (0-20, 0-200, 0-2000, and 0-2kΩ) and supports 2-wire, 3-wire, and 4-wire testing methods. It also includes an earth voltage measuring range of 0-300Vac and automatic spike checks.
| Measuring Ranges Earth Resistance | 0-2, 0-200, 0-2000, 0-2kΩ |
|---|---|
| Earth Voltage Range | 0-300V AC (40 to 500Hz) |
| Accuracy Earth Resistance | +(2%rdg+3dgt) |
| Test Frequency | 820Hz |
| Test Current | 2mA |
| Power Source | 1.5V(AA) x 8 |
| Dimensions | 250(L) x 190(W) x 110(D)mm |
| Weight | Approx. 1430g(battery included) |
The tester requires eight 1.5V AA light batteries.
The operating ambient temperature range is 0 to 50°C (32 to 122°F).