Wiring in a Service Panel Box

WIRING IN AN EXISTING SERVICE PANEL BOX:
The first step in extending your electric service is to determine if there are any blank spaces in your service panel. If not, it may be possible to double up by replacing an existing breaker with a pair of skinnies or a tandem device. In a fuse box you might be lucky enough to find an unused terminal and socket that could be put to work. To wire a circuit breaker or fuse block into an existing service panel, proceed as follows:

1. Turn off the power at the service panel by turning off all main circuit breaker disconnects or removing all main fuses.
2. Remove the screws that hold the panel cover on. Remove the cover.
3. Strip off the outer covering to let the wire reach through a spare knockout and inside the c panel to the proper point of hookup (allow a foot or more of wiring).
4. Run the cable through the knockout with a cable connector and clamp it securely.
5. Run the black wire to the spare circuit breaker or fuse, then strip and connect it.
6. Connect the white wire to the neutral and the bare wire to the ground bar (if there is one) or the neutral.
7. Replace the panel cover. Energize the panel and the individual circuit.
8. Test the circuit. Always use a circuit tester to verify that voltage is present in any circuit on which you have just worked. To use the tester, place one lead on any bare, grounded metal such as an equipment ground terminal, ground wire, or neutral terminal. Carefully touch the other lead to the terminals or wires you are testing for voltage. If the tester bulb glows, voltage is present. To check for voltage on the load side of a main breaker, it may be necessary to test the load terminal of a branch breaker. In this case, the branch breaker must be in the ON position. Check several branch breakers to be sure.