Before using a multimeter to measure whether the circuit is short circuited, first turn off the main switch of the power supply, and then use the 1 or 10 ohm range of the multimeter to measure the two wire ends of the same group of circuits. When the resistance approaches zero, it indicates a short circuit

1. Mechanical zero adjustment

2. Ensure safety

3. Do not shift gears during measurement

4. Horizontal placement

5. Maximum range of AC voltage