Pay attention to the use of safety ground earth impedance tester

Product introduction:

At present, in the power system, the test of the grounding resistance of a large-scale ground network currently mainly uses the power frequency and large current three-pole method. In order to prevent power frequency interference during power grid operation and improve the accuracy of the measurement results, the insulation preventive test regulations stipulate that the test current of the ground frequency grounding impedance tester should not be less than 30 amps. As a result, there have been many problems such as the cumbersomeness of the test equipment, the complexity of the test process, the high strength of the test personnel, and the long test time.

Earth ground network impedance tester + frequency selective voltmeter, measurable substation ground network (4Ω), hydrothermal power plant, microwave station (10Ω), lightning rod (10Ω) multi-purpose models, using a new frequency conversion AC power supply, and using a microcomputer processing Control and signal processing and other measures, the ground network impedance tester during the use of the process to solve the problem of anti-jamming test process, simplifies the test operation process, improve the accuracy and accuracy of the test results, greatly reduced Laborer's labor intensity and test cost.

This instrument is suitable for testing ground frequency impedance, contact voltage, step voltage, and other power frequency characteristic parameters and soil resistivity of various grounding devices. The instrument adopts different frequency anti-interference technology, and can accurately measure the data under the power frequency 50Hz in a strong interference environment. The maximum test current is 5A, which will not cause the potential of the grounding device to be too high during the test. The ground network impedance tester also has strong anti-interference ability during the process of use, so it can be measured without power failure.

Product Features:

â—† The ground frequency impedance tester of the earth network has good power frequency equivalency measured during the use of the precautions. The test current waveform is a sine wave, and the frequency is only 5 Hz out of phase with the power frequency. Measurements are made using 45 Hz and 55 Hz frequencies.

â—† Strong anti-interference ability. This instrument uses the different frequency method to measure, cooperates with the modern software and hardware filtering technology, causes the instrument to have the very high antijamming performance, the test data is stable and reliable.

◆ High precision. The basic error is only 0.005Ω and can be used to measure large ground networks with very small grounding impedance.

â—† powerful. Measurable current piles, voltage piles, grounding resistance, ground net ground impedance tester precautions during use Step voltage, contact voltage.

â—† Simple operation. Full Chinese menu operation directly displays the measurement results.

â—† The wiring has a small amount of labor and does not require a large current line.

Product parameters:

◆ Impedance measurement range: 0Ω～200Ω

◆ Resolution: 0.001Ω

◆ Measurement error: ± (reading × 2% + 0.005Ω)

â—† Resistance to industrial frequency 50Hz voltage interference: 10V

â—† Test current waveform: sine wave

â—† Test current frequency: 45Hz, 55Hz dual frequency

â—† Maximum output current: 5A

â—† Maximum output voltage: 400V

◆ Measurement line requirements: Current line copper core cross-sectional area ≥1mm2

Voltage line copper core cross-sectional area ≥ 1.0mm2

◆ Power supply: AC220V±10%, 50Hz

◆ Dimensions: 440×350×210

â—† Instrument weight: 10kg

Note: If you want to measure the step voltage and electric field gradient, you need to choose frequency voltmeter

Test procedure:

â—† First, check whether the current line, voltage line and grounding wire used in the test are disconnected (can be measured with a multimeter), whether the rust on the ground pile is clean and whether the depth of burial is appropriate (>0.5 meters), and check and test If the connection between the wire and the ground stakes is conductive, if it is not conductive, reconnect it after processing.

â—† The length ratio of the current test line to the voltage test line is 1:0.618. The length of the current test line should be 3-5 times the diagonal of the ground network.

â—† The current test line and the voltage test line are connected to the instrument at a specified length and released in parallel. The other end is connected to two ground piles (as shown in Figure 2).

â—† Check the test line that has been placed once, connect one end of the multimeter to the current line or voltage line, and if the other end of the grounding network cable shows no resistance, it will be an open circuit. Confirm the test and then perform the test.

â—† After checking the connection is correct, connect the instrument to AC220V/50HZ power supply and power on the instrument.

â—† Press the measurement key to start measurement

â—† Record the test data after the instrument displays the test.

â—† After turning off the power of the instrument, remove the connection and the test process ends.