How to Splice Wire Correctly in a Breaker Box
- 1). Strip ¾ inches of insulation from the ends of the conductors. Use caution when using wire strippers to not damage the copper conductors. Grooving the conductor by using the wrong size opening on the stripper will weaken the conductor and decrease its current carrying ability.
- 2). Place the stripped ends side by side and twist tightly together in a clockwise direction with the Electrician's pliers. Continue twisting the wires together until the twisting carries over to the insulated section by three or four twists. Every good electrical connection begins with a solid mechanical connection.
- 3). Screw on a wire nut of the appropriate size. Check to make sure that no bare copper is exposed outside of the wire nut. If necessary, remove the wire nut, cut off a portion of the bare copper, and replace the wire nut. Continue this process until no bare copper shows outside the wire nut.
- 4). Wrap the finished splice with several layers of black, plastic electrical tape, securing the wire nut to the conductors. This step isn't required by the National Electric Code but most professional electricians go this extra step for extra protection. A splice that comes apart in a breaker panel can cause major problems.
- 5). Fold the splice neatly into the panel, pushing it as far to the back of the panel as possible.
- 6). Spread the splices out so they don't violate the 75 percent cross-section fill rule.
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