Switch and hot neutral?
#1
10-03-04, 10:05 AM
Switch and hot neutral?
My son replaced a double wall switch in his new old home. Black in; one black out to wall lamp, the other switch black to garage. Turn on wall lamp or garage separately without problem but if both switches are on, hall lamp goes out garage power not affected. This happens when he uses separate hot circuits in with jumper broken off or single circuit in with jumper connected. Could there be a problem with the neutral circuit? He thought his neutral to the wall lamp was hot when both switches were closed.This is not a three way switch but his garage power goes to a switch as well as a lamp. He does not know if his garage switch is a three way, for sure it never functioned as one as long as he's been there. I'm bringing a meter to help check and would appreciate any tips. Thanks, Charlie
#2
10-03-04, 01:34 PM
One condition that would cause the situation you describe is a "cross" between the Neutral to the hall-lite and the switch-lead to the garage-lite.
When you close the switch to the hall-lite, the hall/garage lites operate in series via the cross-connection. Tracing the circuit, Black wire switch-lead to H-L, thru the H-L to the White wire of the H-L, White wire of H-L to Black wire switch-lead of G-L, (cross) , Back wire switch-lead to G-L, thru the G-L to the White wire of the G-L, completing a series-circuit.
When you close both switches, the 2 switches "short-circuit" the H-L--- "Feed" Black-wire thru the H-L switch to the Black wire switch-lead to the H-L, thru the H-L to the H-L White wire, thru the H-L White wire to the Black wire switch-lead to the G-L (cross), thru the Black-wire switch-lead of the G-L to the G-L switch, thru the G-L switch back to the "Feed" Black, connecting the Black "Feed" wire to both fixture leads of the H-L.
When you close the switch to the hall-lite, the hall/garage lites operate in series via the cross-connection. Tracing the circuit, Black wire switch-lead to H-L, thru the H-L to the White wire of the H-L, White wire of H-L to Black wire switch-lead of G-L, (cross) , Back wire switch-lead to G-L, thru the G-L to the White wire of the G-L, completing a series-circuit.
When you close both switches, the 2 switches "short-circuit" the H-L--- "Feed" Black-wire thru the H-L switch to the Black wire switch-lead to the H-L, thru the H-L to the H-L White wire, thru the H-L White wire to the Black wire switch-lead to the G-L (cross), thru the Black-wire switch-lead of the G-L to the G-L switch, thru the G-L switch back to the "Feed" Black, connecting the Black "Feed" wire to both fixture leads of the H-L.
