Color screen earth network grounding resistance tester

Color screen earth network grounding resistance tester

Introduction

At present, in the power system, the grounding resistance of large grounding grids is mainly measured using the power frequency high current three pole method. In order to prevent power frequency interference during the operation of the power grid and improve the accuracy of measurement results, the insulation preventive test regulations stipulate that the test current of the power frequency high current method shall not be less than 30 amperes. As a result, there are many problems such as bulky testing equipment, complex testing processes, high workload of testing personnel, and long testing times.

Multi purpose models including substation grounding network (4 Ω), hydro thermal power plant, microwave station (10 Ω), and lightning rod (10 Ω) can be tested. A new type of variable frequency AC power supply is used, and measures such as microcomputer processing control and signal processing are adopted to effectively solve the anti-interference problem during the testing process. The experimental operation process is simplified, the accuracy and precision of the test results are improved, and the labor intensity and testing cost of the testing personnel are greatly reduced.

This instrument is suitable for testing the power frequency grounding impedance and other power frequency characteristic parameters of various grounding devices, as well as soil resistivity. This instrument adopts cross frequency anti-interference technology, which can accurately measure data at the power frequency of 50Hz in strong interference environments. The test current Z is greater than 5A, which will not cause the potential of the grounding device to be too high during testing. At the same time, it also has anti-interference ability, so it can be measured without power outage.

Color screen earth network grounding resistance tester

Performance characteristics

1. The measured power frequency equivalence is good. The test current waveform is a sine wave, with a frequency difference of only 5Hz from the power frequency. Two frequencies, 45Hz and 55Hz, are used for measurement.

2. Strong anti-interference ability. This instrument adopts the frequency difference method for measurement, combined with modern software and hardware filtering technology, making the instrument have high anti-interference performance and stable and reliable test data.

3. High precision. The basic error is only 0.005 Ω, which can be used to measure large grounding grids with very low grounding impedance.

4. Function *. It can measure the grounding resistance of current piles, voltage piles, grounding resistance of grounding grids, conductivity resistance, and soil resistivity.

5. Easy to operate. Fully Chinese menu style operation, directly displaying measurement results.

6. Low wiring workload, no need for high current wires.

technical indicators

1. Impedance measurement range: 0-5000 Ω

2. Resolution: 0.001m Ω

3. Measurement error: ± (reading x 2%+0.005 Ω)

4. Test current waveform: sine wave

5. Test current frequency: 45, 50, 55, 60, 65Hz single frequency

45/55Hz, 55/65Hz, 47.5/52.5Hz automatic dual frequency conversion

6. Output current: 1, 2, 3, 4, 5A

7. Z output voltage: 400V

8. Measurement line requirement: The cross-sectional area of the copper core of the current wire should be ≥ 1.5mm2

Voltage wire copper core cross-sectional area ≥ 1.0mm2

9. Power supply: AC180-270V, 50/60Hz

10. Dimensions: 355 × 335 × 340mm Instrument weight: 18kg