If you use large appliances in your home, such as a dryer, they require a 240v circuit breaker. A 240v volt circuit breaker is similar to a standard circuit breaker, except it has two breaker switches placed on top of each other. Installing a new 240v circuit breaker is a project that can be tackled by a beginning DIY person. Here are some tips to install a 240v circuit breaker.
Prepare to Work
For this project, you need:
- work gloves
- voltage tester
- utility knife
- wire stripper
- 40 amp cable
- 240v breaker
Open the breaker panel, switch all breakers off, and look for the breaker switch that says "Main". The "Main" breaker switch commonly has two black wires running to it from the electrical meter. It should also have the total amperage of the panel marked beside it.
Run a voltage tester over the panel to ensure no current is present.The voltage meter will blink or beep when it detects a current. If you get a current, wait several minutes and test again, since currents may remain a while after the power is off.
Connect the Cable
Trim four inches from the jacket around the cable with the utility knife, taking care not to cut wires. You should see four wires, white (neutral), red (hot), black (hot), and ground (copper or green). Strip about a quarter inch of sheathing from the inner wires, using the wire strippers.
Remove the screw on each side of the breaker. Place the tip of the red wire around one screw, and wrap the tip of the black wire around the other screw.
Insert the Breaker
Use the slotted screwdriver to loosen the screws on the panel. Take off the cover, and set the screws and panel aside. Remove two knock out tabs using the screwdriver blade, and then pull the tab with pliers.
Shine a flashlight on the panel, and rock the breaker back and forth into a slot on the hot bus, or where the breakers sit. Press the breaker until you hear a click.
Loosen two screws on the neutral bus, or metal strip with silver screws. Attach the green or copper ground wire to one screw, and white wire to the other, then tighten the screws. Connect the other end of the cable to the appliance.
Reinstall the breaker panel cover, turn the power back on, and test the appliance. If you don't trust your skill, or the unit fails to work, contact Conway Electric or your local electrician.