How to use the multimeter to check the line
When charged, use AC voltage or DC voltage according to the situation! Use electrical barriers to detect circuit paths and short circuits without dots!
The multimeter has a buzzer block, which is to use two test leads to measure the same wire. If there is a short circuit, there will be no response. If it is a circuit, there will be a buzzing sound. Sometimes when the device itself is charged due to poor grounding, you can use the red test lead of the multimeter to place it on the black mark on the case. Compared with direct contact with the ground, the strength of the leakage electrical appliance of the shell can be measured, so that it can be known in the rest of the work. It is also connected in series to the circuit to measure the AC and DC current.
To check whether the circuit is leaking or not, you must use a megohmmeter (shaking meter), because the voltage of the multimeter is low (9v), and the voltage of the megger is 500v. Because the working voltage of the line is 220v, it is difficult to diagnose the line with no obvious leakage. If you want to use a digital meter to check the line leakage, you need to cut off the power supply first, and after discharging the line, use the resistance gear, 2M gear to measure, and the normal display is 1 (infinite).
To measure whether the line is connected, you can use a multimeter to measure the ohm range. When measuring, choose the position where the pointer of the ammeter is close to deflecting 0 ohms. If the line is in the circuit, connect one end (A end) of the line to the 100 ohm range of the multimeter (red test pen), and connect the black test lead to the other end (B end) of the line to be measured. If the measured result is zero, it means this A connected line is also called a path. Only through a path can current flow through the circuit; if the pointer of the multimeter ohm range meter is not close to zero ohms from the A end to the B end of the line, the line is already in an open state, and disconnection is called open circuit or open circuit.
