Electrical Questions? Ask an Electrician Online.
Hello and welcome to Just Answer. My name is ***** ***** I will be happy to assist you with your electrical question.
1) What was the wiring scheme that was installed on the original dryer circuit? Romex cable or BX cable or conduit?
2) Have you visually traced from where the original 2 hot wires that terminated to the 30 amp breaker? Do the 2 original hot wires end up in the same cable sheath or the same conduit? If so, you should be able to locate the corresponding white neutral wire?
3) Take a look at the neutral bus bar. The original white dryer neutral would have been a 10 AWG white copper wire. Process of elimination, doubt that the neutral bus bar contains too many 10 AWG white neutrals landing there?
4) Yes, the unused original hot wires can be capped off inside the main panel, that is not a problem.
Thank you for the replies and the pic's.
1) You mentioned that the duplex originally had 3 wires terminating to it.........ie..... 2 blacks and 1 white. Sounds like this receptacle was split wired since only 1 white neutral. Most likely 1/2 of the receptacle was always live and the other 1/2 was switched. Thus the reason only 1 white neutral existed.
2) If re-using the same 2 black wires onto a switch or to the light fixture, the circuit breaker tripped due to a direct short circuit.
3) In order to confirm the functionality of the 2 black and 1 white wires, you will need either a 2 wire lead AC voltage tester (a contact type) or an AC voltmeter.