Multimeter detects short circuit, open circuit and grounding, with tips on short circuit and open circuit
With a small multimeter, you can detect whether there is a short circuit or open circuit in the circuit. You can also use the multimeter to measure whether it is grounded, whether there is a path, etc. There is some knowledge about short circuit and open circuit at the end of the article for your reference.
1. Short circuit
Turn off the power before measuring, use the ohm rail of the multimeter to measure, and use the red and black test leads to measure the live wire and ground wire. If the resistance of the meter is low, it means there is a short circuit.
2. Break circuit
When measuring an open circuit, keep the power on, use the voltage switch of the multimeter to measure, and use the red and black test leads to measure the live wire and ground wire. If the meter reaches zero voltage, it is an open circuit.
3. Grounding
When measuring whether the circuit is grounded, it should be carried out when the circuit is energized. Use the voltage barrier to measure. The red and black test leads measure the live wire and the ground wire. If the meter has voltage, it means it is grounded. If the meter has no voltage, it means it is not grounded.
4. Access
It is also very convenient to use a multimeter to check whether there is a path. There is a certain resistance and a buzzing sound. Short circuit: resistance is zero. There is a beep. Open circuit: infinite resistance. No beeps.
what is short circuit
A short circuit is when a circuit or part of a circuit is short-circuited. If the load and the power supply are connected together by a wire, it is called a short circuit.
The current is very large during a short circuit, and the current provided by the power supply during a short circuit is much greater than the current provided by the path.
Under normal circumstances, short circuit is not allowed. If the short circuit is serious, it will burn out the power supply or electrical equipment.
What is circuit break
Broken circuit (open circuit) refers to a state in which the circuit does not have a closed switch, or the wires are not connected properly, or the electrical appliance is burned out or not installed properly (such as connecting a voltmeter in series with the circuit), that is, the entire circuit is disconnected somewhere.
