1, the two **** the same point:
1) DC withstand voltage test and leakage current test measurement method and wiring is basically the same;
2) the two added voltage is also the same.
2, the two differences:
1) focus on the assessment of different purposes:
DC withstand voltage is mainly to assess the generator's insulation strength, such as insulation with or without air gaps or damage, etc.;
Leakage current is mainly a response to the overall wire rod insulation with or without moisture, dirt, deterioration, but also react to the rod end of the surface of the cleanliness of the situation.
2) the difference in pressurization time:
DC withstand voltage test pressurization time is longer; leakage current test pressurization time is shorter.
Leakage current test is to check the insulation moisture, dirty and conductive channels and so on, so the test voltage is lower, the pressurization time is also shorter.
3) different significance:
DC withstand voltage test for the discovery of bubbles, mechanical damage and other local defects of special significance;
Leakage current test on the response to the insulation as a whole of the moisture, deterioration, etc. more sensitive.
Expanded information:
1, the concept of:
1) DC withstand voltage test, belongs to the destructive test, the test process will be on the equipment to a certain degree of Damage, in order to detect the maximum voltage peak value of the equipment to withstand under high-voltage test. Facilitate the determination of the scope of use of the equipment and select the range of the equipment.
2) leakage current test, the test of electrical equipment insulation plus a certain amount of AC voltage, under this voltage, measure the insulation to ground and the leakage current between phases, in order to determine the insulation condition of the equipment method.
2, DC withstand voltage test procedure:
1) DC withstand voltage test device should be checked before use of its integrity, the connecting cable should not be disconnected and short-circuited, the equipment is not ruptured and other damage.
2) Place the chassis, times the pressure tube to the appropriate location were connected to the cable, ground wire and power cord, protective ground wire and work ground wire and the ground wire of the discharge rod should be individually connected to the ground of the test specimen (i.e., a point of grounding).
It is forbidden to connect the grounding wires in series with each other, for this reason, ZGF special grounding wire should be used.
3) The power switch is placed in the off position and check the voltage regulator potentiometer should be in the zero position. Overvoltage protection setting value is generally 1.1 times the test voltage.
4) No-load voltage test over-voltage protection setting is sensitive.
5) Turn on the power switch, the green light is on, indicating that the power supply is on.
6) Press the red button, the red light is on, indicating that the high voltage is on.
7) Adjust the voltage regulating potentiometer in clockwise direction gently, the output will be boosted from zero, and after it rises to the required voltage, record the ammeter reading according to the specified time, and check the control box and high-voltage output line for any abnormality and sound.
8) Decrease the voltage, the voltage regulator potentiometer back to zero, then press the green button, cut off the high voltage and turn off the power switch.
9) Leakage and DC withstand voltage test on the specimen. After checking the test to confirm that the tester is not abnormal, you can start the specimen leakage and DC withstand voltage test. Connect the test specimen and ground wire, and turn on the power after checking that there is no error.
10) Boost to the required voltage or current. Boosting speed to 35KV test voltage per second is appropriate. For large capacitance specimen boosting also need to monitor the ammeter charging current does not exceed the maximum charging current of the tester.
Small capacitance test specimens such as zinc oxide surge arrester, magnetic blowing surge arrester, etc. first to 95% of the required voltage (power), and then slowly and carefully up to the required voltage (current), and then read out the voltage (current) value from the digital display meter.
If you need 0.75UDC1mA measurement of zinc oxide lightning arrester, first rise to the UDC ~ 1mA voltage value, and then press the yellow button, then the voltage is reduced to 75% of the original, and to maintain this state. At this time can be read microamps.
After the measurement is completed, the regulator potentiometer counterclockwise back to zero by pressing the green button. Press the red button when you need to boost the voltage again.
If necessary, use an external high-voltage voltage divider to compare the DC high voltage indication on the control box.
11) When the test is finished, lower the voltage and turn off the power.
12) For zinc oxide lightning arrester and other small capacitance specimens are generally discharged through the voltage measuring resistor time is very fast. The cable and other large capacitance specimens generally to wait until the specimen voltage self-discharge to the test voltage of less than 20%, and then through the supporting discharge rod discharge.
To be fully discharged after the specimen hung up the grounding wire, before allowing the removal of high-voltage leads and replacement of wiring work. 13, the operation of the protection action in the use of the process found that the red light off, green light, voltage drop, that is, the protection action.
This time should turn off the power switch, the panel lights are not lit. Return the voltage regulator potentiometer to zero, one minute after the machine to be fully discharged low-voltage capacitors before being allowed to open the power switch again. Re-carry out no-load test and find out the situation can be again after the voltage test.
3, the purpose of the experiment:
DC withstand voltage test: the maximum voltage peak
Leakage current test: to determine the insulation condition of the equipment
Baidu Encyclopedia - DC withstand voltage test
Baidu Encyclopedia - Leakage current test