Grounding Resistance Tester

At present, if we use traditional way to test earth resistance of geodetic network . we should avoid power frequency interference generated by power grid during operation and improve the accuracy of measurement value.Meanwhile,the insulation preventive test specifications stipulate: the test current of power frequency heavy current method should not be less than 30A. Thus cumbersome test equipment, complicated test process, heavy working strength of testers, long test time and other many problems appeared.

Model HM3001(5A) Grounding Resistance Tester adopts new type variable frequency AC power supply and microcomputer processing control, signal processing and other measures, which can properly solve the interference problem during test, simplify test operating process, improve precision and accuracy of test results.

1.Good power frequency equivalence of measurement. Test current waveform is sine wave, the difference between frequency and power frequency is only 5Hz, measure with 45Hz and 55Hz frequency.

2.Strong anti-jamming capacity. with pilot frequency measurement method and modern software and hardware filter technique, enabling the device to have very high anti-jamming performance, thus achieving stable and reliable test data.

3.High precision. Intrinsic error is only 0.005Ω, which can be used to measure the geodetic network with very small earth resistance.

4.Powerful functions. Able to measure current pile, voltage pile, earth resistance, step voltage and contact voltage.

5.Simple operation. Full English menu operation, directly display the measurement results.

6.Small amount of wiring labour, requiring no heavy current line.

Measurement scope: 0～200Ω (including impedance of current pile)

Resolution: 001Ω

Measurement error: ± (reading×1%+0.005Ω)

Maximum output voltage: AC 400V (45Hz, 55Hz, double frequency, sine wave)

Maximum output current: AC 5A (45Hz, 55Hz, double frequency, sine wave)

Current output gears: 5/4.5/4/3.5/3/2.5/2/1.5/1A，, one gear every 0.5A, totalling 9gears.

Anti-jamming capacity: power frequency resistance 50Hz voltage 10V

Requirement for measuring line:

Sectional area of cooper core of current line≥1.5mm²

Sectional area of cooper core of voltage line≥1.0mm²

Electric power supply: AC 220V±10%, 50Hz

Contour dimension: 320×350×315mm3

Instrument weight: 27.5kg

Fig. 1 Diagram of Measurement Wiring with Three-Electrode Method

Measuring current line D: line diameter ≥1.5mm² ,the length is 3～5 times as long as length of diagonal of earth network;

Measuring voltage line 1: line diameter≥1.0 mm² , length 0.618D;

Measuring voltage line 2: connect measured earth network

Measuring earthing line: connect measured earth network

Fig. 2 Diagram of Measurement Wiring with Four-Electrode Method

When measuring with four-electrode method, lead out two connecting lines from the earth pile of earth network to be respectively connected to two connecting poles of voltage electrode P2 and earthing network C2 of the instrument, then conduct test according to measurement operating steps.

1.Our company is a high-tech enterprise in Wuhan Economic High-tech Development Zone, Hubei,china.

2.Our factory is mainly engaged in R&D,production and sales of power high voltage test equipment,substation on-line detection system and other electric test device.

3.Our factory has a quality inspection department, all of our product will do factory test before delivery,to ensure the quality and reliability of our goods.

5.Our factory set a special technical support department to ensure fast and efficient after-sales service channels