Precautions for the hottest grounding resistance m

Precautions for grounding resistance measuring instrument

the grounding resistance measuring instrument abandons the traditional manual power generation mode, adopts advanced medium and large-scale integrated circuits, and applies dc/ac conversion technology to combine the three terminal button and four terminal button measurement methods into a new type of grounding resistance measuring instrument, with a year-on-year increase of 14.71%

the working principle is that the dc/ac converter in the machine converts DC into AC low-frequency constant current, which forms a circuit through the auxiliary grounding electrode C and the measured object e. the AC voltage drop is generated on the measured object, which is sent to the AC amplifier through the auxiliary grounding electrode P. in recent years, the amplifier is amplified, and then sent to the meter for display after detection. The reason is that in the last century, special engineering plastics have been listed as strategic material multiplier switches, and three different limits can be obtained: 0-2 Ω, 0-20 Ω, 0-200 Ω

main features

1. The structure adopts high-strength aluminum alloy as the shell, and the circuit adopts phase-locked loop synchronous tracking detection mode and equipped with switched capacitor filter to prevent power frequency and RF interference, so that the instrument has better anti-interference ability

2. Adopt dc/ac conversion technology to change DC into AC low-frequency constant current for easy measurement

3. The auxiliary grounding resistance is allowed to change between 0-2k Ω (RC) and 0-40k Ω (RP), which will not affect the measurement results

4. The grounding resistance measuring instrument does not need to adjust the balance manually. The 3 (1/2) LCD display can measure the resistance of low resistance conductors, soil resistivity and AC ground voltage in addition to the grounding resistance

5. If the test circuit is not connected, the header displays "1" for overflow, which conforms to the routine measurement habit

precautions

1 When storing and keeping this form, attention should be paid to the ambient temperature and humidity. It should be placed in a dry and ventilated place to avoid moisture, acid, alkali and corrosive gases

2. When measuring the protective grounding resistance, be sure to disconnect the electrical equipment from the power connection point. When measuring the grounding resistance less than 1 Ω, connect it to the grounding body with special wires, C2 on the outside and P2 on the inside

3. When measuring the grounding resistance of large-scale grounding, it cannot be measured according to the general wiring method, and the buried points can be selected according to the provisions of ammeter and voltmeter measurement method

4. When measuring the ground resistance, it is best to measure it repeatedly in different directions for 3-4 times, and take the average value

5. This instrument is used for both AC and DC. When AC is not connected, the instrument uses battery power supply. When AC is connected, AC is preferred

6. When "←" is displayed in the upper left corner of the meter, it indicates that the battery voltage is insufficient and should be replaced with a new battery. When the instrument is not used for a long time, take out all the batteries to avoid rusting the instrument

product advantages

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

2. It has strong anti-interference ability. The instrument adopts different frequency method for measurement, and cooperates with modern software and hardware filtering technology, so that the instrument has high anti-interference performance. When the test encounters faults, it can be called to analyze various data. The data is stable and reliable

3, and the accuracy is high. The basic error is only 0.005 Ω, which can be used to measure large grounding

4 with small grounding impedance, and has powerful function. It can measure current pile, voltage pile, grounding resistance, step voltage, contact voltage

5, and the operation is simple. Full Chinese menu operation, direct display of measurement results

6, less wiring labor, no need for large current lines