How to measure whether there is leakage with digital multimeter
Leakage measurement method
First, disconnect the main isolating switch of the user's power supply, and turn off all the power loads of the user, such as unplugging the refrigerator and disconnecting the water pump switch.
Put the gear of the digital multimeter on the 200M gear of the ohm gear, put one stylus on one of the two outgoing lines on the load side, and touch the wall with the other stylus, preferably touching the grounding wire or temporary grounding wire. After the number displayed on the multimeter is stable, the insulation resistance value of the main line is read out. If the insulation resistance value is less than 0.5 megohm, there is something wrong with the main line. If the insulation resistance is above 0.5 megohm, it can be ruled out that there is something wrong with the main line. Measure the other wire in the same way, and also check the value to see if there is something wrong with the main line.
Check the insulation resistance values of the shunt and all electrical appliances, and test them one by one in the same way until the fault point is found.
Precautions for operation
When using the 200M block of the multimeter ohm block, be careful not to touch the metal part of the stylus with your hands when measuring.
That will make the reading inaccurate.
Pay attention to discharge before measuring each electrical equipment to prevent the capacitive current in the electrical equipment from hurting people.
This method is a safe way to find the fault point when there is no electricity. This method is also suitable for power.
Household and factory leakage search, but in search, not only to disconnect the power supply into the line, but also to disconnect the zero line.
Multimeter can be used to measure not only the resistance of the measured object, but also the AC and DC voltage. Even some multimeters can measure the main parameters of transistors and the capacitance of capacitors. Fully mastering the use of multimeter is one of the most basic skills of electronic technology.
Common multimeters include pointer multimeter and digital multimeters. The pointer multimeter is a multifunctional measuring instrument with the meter head as the core component, and the measured value is read by the pointer on the meter head. The measured values of digital multimeter are displayed directly in digital form by LCD screen, which is convenient to read, and some of them also have voice prompt function. Multimeter is a common meter that integrates voltmeter, ammeter and ohmmeter.
The DC current file of multimeter is a multi-range DC voltmeter. The voltage range of the meter can be expanded by connecting the closed-circuit voltage divider in parallel. The DC voltage range of multimeter is a multi-range DC voltmeter. The voltage range of the meter can be expanded by connecting the voltage divider resistor in series. Different voltage dividing resistors have different corresponding ranges. The meter head of the multimeter is magnetoelectric measurement *, which can only change AC into DC by using diodes, thus realizing the measurement of AC.
