What file should the leakage multimeter play? How to use a multimeter to check leakage
How to measure leakage with a multimeter
The battery inside the multimeter is 9v to 15v. The resistance and voltage files can only determine the short circuit, and roughly judge whether there is leakage.
There are three ways to check leakage with a multimeter:
1. Power-off measurement: turn off and disconnect all electrical appliances, use a multimeter with RX10K gear, one test lead is connected to the live wire, and the other test lead is grounded (or faucet). It should show infinite resistance, otherwise there will be leakage.
2. Live measurement: Use a multimeter with a 250-volt AC voltage range to measure the metal shell of the electrical appliance that is suspected of leakage. One test lead is connected to the shell, and the other test lead is grounded (or the faucet). When the pointer shows a voltage higher than 30-50 volts, replace it Use AC 50 volts. If the power supply is confirmed to be higher than 30 volts, it is a leakage, and lower than 30 volts is normal. Then swap the zero and fire power supply plug wires and measure again to confirm.
3. Leakage measurement between live wire and neutral wire (or live wire and live wire): turn off and disconnect all electrical appliances, measure the resistance between live wire and neutral wire, it should be infinite, otherwise it is leakage.
Caution
1. Before using the multimeter, "mechanical zero adjustment" should be performed first, that is, when there is no electricity to be measured, make the pointer of the multimeter point to the position of zero voltage or zero current;
2. In the process of using the multimeter, do not touch the metal part of the test lead with your hands, so that on the one hand, it can ensure the accuracy of the measurement, and on the other hand, it can also ensure personal safety;
3. When measuring a certain amount of electricity, it is not possible to change gears while measuring, especially when measuring high voltage or high current, more attention should be paid. Otherwise, the multimeter will be destroyed. If you need to change gears, you should disconnect the test leads first, and then measure after changing gears;
4. When using the multimeter, it must be placed horizontally to avoid errors. At the same time, it is also necessary to avoid the influence of the external magnetic field on the multimeter;
5. After using the multimeter, the transfer switch should be placed in the maximum gear of the AC voltage. If it is not used for a long time, the battery inside the multimeter should also be taken out to prevent the battery from corroding other components in the meter.
How to use a multimeter to measure leakage with which gear
1. Power-off measurement: turn off and disconnect all electrical appliances, use a multimeter with RX10K gear, one test lead is connected to the live wire, and the other test lead is grounded. It should show infinite resistance, otherwise there will be leakage.
2. Measurement with a point: Use the 250V AC voltage range of the multimeter to measure the metal casing of the electrical appliance that is suspected of leakage. One test lead is connected to the casing, and the other test lead is grounded. When the pointer shows that the voltage is higher than 30-50V, switch to AC 50V. If the power supply is confirmed to be higher than 30V, it is a leakage, and lower than 30V, it is normal, and then the zero and fire power supply plug wires are reversed and measured again to confirm.
3. Leakage measurement between live wire and neutral wire (or live wire and live wire): turn off and disconnect all electrical appliances, measure the resistance between live wire and neutral wire, it should be infinite, otherwise it is leakage.
