How to Test a Circuit Breaker with a Multimeter
A broken circuit breaker increases the risk of an electrical overload occurring in your home. An overload can cause a short circuit to occur, breaking your devices and appliances. In extreme cases, electrical shorts can even pose a fire risk.
Testing a circuit breaker is necessary to determine the flow of electricity in a circuit breaker panel. The most efficient way to test a circuit breaker is with a multimeter. A multimeter is an instrument that combines several measurement functions in one unit to provide useful readings. Multimeters can measure volts, amps, and ohms through outlets, fixtures, and breakers, making them an important tool for any aspiring electrician.
If you’ve recently purchased a multimeter to carry out basic electrical work, or are just curious about how these important devices work, read on. We’ll explain how electricians use multimeters to test and replace circuit breakers.
Testing a Circuit Breaker with a Multimeter
Here are the steps an electrician will follow to test your circuit breaker with a multimeter:
- First, the electrician will make sure the area around the electrical panel is dry. If there is any standing water on the ground, the service professional will mop it up before opening the electrical panel.
- To check a breaker with a multimeter, the electrician will open the circuit breaker box and determine which breaker will be tested.
- The electrician will then turn off all lights and appliances that are being powered through the circuit breaker being tested.
- The AC volts setting (usually abbreviated “ACV”) is the multimeter setting the service technician will use to test the circuit breaker.
- They will touch one prong of the multimeter to the breaker’s terminal screw and touch the other prong to a ground screw. The ground screw is usually located in a metal bar along the right-hand side of the electrical panel.
- Once these prongs are connected, the readout on the multimeter will display the potential voltage at the breaker position.
- If the reading is zero, then the breaker is faulty and need to be replaced.
Because circuit breakers and electrical panels pose a lethal shock risk, only a licensed electrician should test, diagnose, or service your circuit breakers!
