Get the Mobile Home Electrical Parts You Need NOW!
Testing circuit breaker with a volt meter or digital multimeter to test the breakers inside the circuit breaker panel box is the best way to determine if you have a bad breaker. Testing single pole 120 volt or a double pole 240 volt breakers with a voltage tester and taking voltage measurements is the best way to determine if the circuit breaker is bad and if you need to replace any circuit breakers. When using a volt meter to test circuit breakers always be sure that the setting on the volt meter is higher than the voltage that you will be testing. While I was testing I had my digital multimeter set to the 600 volt scale so as not to damage my voltmeter. I recommend using a digital volt meter when doing a voltage test because they are easier to read. If you don't have one you can get one inexpensively. The circuit breaker test procedures described apply to all brands including Murray, GE-General Electric, Challenger, Square D, ITE, Zinsco, FPE- Federal Pacific, Seimens, Bryant or most any other type of circuit breaker that you believe you are having problems with. When working in a live circuit breaker box be extremely careful. I recommend wearing gloves and long sleeves. Use common sense such as avoiding damp or wet locations. Always use safety procedures and be alert so as not to come in contact with any live surfaces. If you are unsure about troubleshooting these problems get a qualified electrician.
Main circuit breaker test
Shown in the pictures below is how to take voltage measurements at the main circuit breaker to determine if you have 240 volts coming into the circuit breaker panel box. The test points shown in the pictures are across both poles, which should give you 240 volt reading and also testing from one pole of the breaker to the ground buss bar which should give you 120 volt reading on your digital multimeter.
Across both poles you should measure about 240 volts and from either the top or bottom pole to the ground buss bar should be about 120 volts. If you have no voltage or extremely low voltage on any of these readings then you either have a problem in the wiring connections, a problem with the outside main breaker panel or a problem on the power company side. This could even mean a problem with the transformer.
Double pole circuit breaker test
Shown in the pictures below is how to test double pole circuit breakers to determine if both poles of the circuit breaker are working. Sometimes one pole of the double pole breaker will stop working causing devices or appliances such as dryer, stove, a/c, heater or water heater to stop operating properly. Testing a double pole appliance circuit breaker is the same as testing the main circuit breaker. The test points shown in the pictures are across both poles, which should give a 240 volt reading and also testing from one pole to the ground buss bar should give you a 120 volt reading using your volt meter.
As with the main breaker I have tested across both poles and should have a voltage measurement of about 240 volts. From one pole at a time to ground buss bar should give you a voltage measurement of about 120 volts.
Test Circuit Breaker Single Pole 120 Volt
Testing a circuit breaker for situations when you either have a circuit breaker that is tripped or you have a circuit that has lost power is a common problem. You can look at the page for a circuit breaker that is tripping for more information. The pictures below show testing a circuit breaker by doing a voltage test from the connection where the wire attaches at the circuit breaker and at the ground buss bar. If you have a circuit breaker that is tripping as soon as you turn it on I suggest that you swap it with one in the circuit breaker box that is working properly to rule out a weak circuit breaker. Some circuit breakers can become weak over time causing them to trip at levels below their rated values.
If a test indicates a bad circuit breaker then it is time to replace it. You can go to my parts page or get one in most cases, unless it is a hard to find brand, at your local home or hardware store. If you choose to go to your local supply store take the old circuit breaker with you to match it up. When you go to remove the breaker for replacement turn off the main circuit breaker on the outside. Turning off the inside main breaker does not kill the power to the inside of the panel box at the main breaker connections.
All the to test a circuit breaker and voltage checks on this page apply to site built, modular as well as mobile homes, manufactured homes and RVs.
How to Test Circuit Breaker
Any Questions or Comments Please Contact Me
Website Authored by Don Morgan