I．Introduction
Earth Resistance Tester is also called double clamp grounding resistance tester. The advanced grounding resistance tester integrates a variety of measurement methods. In addition to the traditional function of ancillary grounding resistance, it also has the unique function of measuring without auxiliary ground. It uses a large LCD gray screen backlight display and microprocessor technology, through the microprocessor control precision 4-wire method, 3-wire method and simple 2-wire method, selection method, double clamp method to measure grounding resistance test. Large-diameter current clamp design, using double jaw measurement technology, without the need to hit the auxiliary ground, without the need to isolate the grounding body and equipment to achieve on-line measurement.Suitable for telecommunications, electricity, meteorology, computer rooms, oil fields, power distribution lines, iron tower transmission lines, gas stations, factory grounding networks, lightning rods and so on. Instrument testing is precise, fast, simple, stable and reliable.
Earth Resistance Tester is controlled by the microprocessor and can accurately detect the grounding resistance, soil resistivity, grounding voltage, DC resistance and AC current. It uses a fast filtering technique to minimize interference. The resistance value of the auxiliary electrode is displayed on the same screen to facilitate the determination of the measurement error due to environmental factors, and it is convenient to measure the true grounding resistance more accurately.At the same time store 500 sets of data,online monitoring data through monitoring software, USB data uploaded to PC and unique features such as intelligent alarm alert.
Earth Resistance Tester consists of host, monitoring software, test line, USB cable, and grounding rod. It has the functions of reading, checking, saving, reporting and printing of historical data.
II. Rang and Accuracy
Test Function |
Range |
Accuracy |
Resolution |
2、3、4 wire method for measuring ground resistance (Re) |
0.00Ω～29.99Ω |
±2%rdg±5dgt(remark 1) |
0.01Ω |
30.0Ω～299.9Ω |
±2%rdg±3dgt |
0.1Ω |
|
300Ω～2999Ω |
1Ω |
||
3.00kΩ～30.00kΩ |
10Ω |
||
DC resistance(Re) |
0.0Ω～299.9Ω |
±2%rdg±3dgt |
0.1Ω |
300Ω～2999Ω |
1Ω |
||
3.00kΩ～30.00kΩ |
10Ω |
||
Selection method for measuring ground resistance(Re) |
0.00Ω～29.99Ω |
±2%rdg±5dgt(remark 1) |
0.01Ω |
30.0Ω～299.9Ω |
±2%rdg±3dgt |
0.1Ω |
|
300Ω～3000Ω |
1Ω |
||
Double clamp method for measuring ground resistance (Re) |
0.01Ω～0.99Ω |
±10%rdg±10dgt |
0.01Ω |
1.0Ω～9.9Ω |
0.1Ω |
||
10Ω～100Ω |
1Ω |
||
Soil resistivity(ρ) |
0.00Ωm～99.99Ωm |
ρ=2πaR (注2) |
0.01Ωm |
100.0Ωm～999.9Ωm |
0.1Ωm |
||
1000Ωm～9999Ωm |
1Ωm |
||
10.00kΩm～99.99kΩm |
10Ωm |
||
100.0kΩm～999.9kΩm |
100Ωm |
||
1000kΩm～9999kΩm |
1kΩm |
||
Ground voltage |
AC 0.00～100.0V |
±2%rdg±3dgt |
0.01V |
AC current |
AC 0.0mA～1000A |
±2%rdg±3dgt |
0.1mA |
Remark：
1. Reference conditions: accuracy with Rh Rs < 100Ω.
Working conditions:Rh max＝3kΩ+100R＜50kΩ；Rs max＝3kΩ+100R＜50kΩ
2.Depends on the measurement accuracy of R,π=3.14, a:1 m～100m;