How to Test a 220 Volt Circuit Breaker

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Things You'll Need

  • Screwdriver

  • Multimeter

Always take great care when working with electricity.

Electricity enters your home from the power supply company through two 110- to 120-volt cables and is fed into the electrical supply box. Most appliances in the home run off 110 volts, but some appliances that draw more power need 220 volts to work. A 220-volt circuit breaker draws its power from each of the two supply lines, and it is double the width of a normal 110-volt circuit breaker. It has two input and two output wires, although it can draw its power from two 110-volt bus bars to which it is connected and just have the two output wires. When a 220-volt circuit breaker continues to trip, you need to test it.

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Initial Test

Step 1

Open up the electrical box and shut off the main switch.

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Step 2

Disconnect the wires that feed from the circuit breaker that has tripped.

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Step 3

Switch on the circuit breaker. If it immediately trips and will not switch on, the 220-volt circuit breaker is faulty. If it does not trip again, go to Section 2.

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Second Test

Step 1

Disconnect the wires from one of the 220-volt circuit breakers that is working correctly. This circuit breaker must be of the same or lower amperage as the circuit breaker that is tripping, never greater. Connect the disconnected wires from the tripping circuit breaker to the second circuit breaker.

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Step 2

Turn on the main power switch. If the second circuit breaker trips, the problem is definitely in the wiring circuit, and there is nothing wrong with your first circuit breaker.

Step 3

Switch on all of the lights, appliances and devices on the second circuit breaker if it does not trip initially. If the second circuit breaker does not trip, the first switch is faulty.

Warning

Electricity is dangerous. Electrical boxes can sometimes be wired incorrectly and in such a way that any wire could be live. If you are uncertain about how to go about this process, call an electrician. Better to be safe than sorry.

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