DaveHo
Supporting Actor
- Joined
- Dec 11, 2001
- Messages
- 605
I'm pretty sure we have a few electricians on this forum. Hopefully one of you will spot this.
This is kind of complicated so I'll do my best.
I was replacing an outlet powered by breaker #1. I shut off breaker #1, and confirmed the outlet had "no power" via a light. This duplex had 3 14/2 with ground wires going to it. They were not pigtailed but connected via the back stabs & side wire terminals. As I began disconnecting the neutrals, I noticed some sparks and the ceiling light in the adjacent room flickering. That light was not on the same breaker. I flipped off the breaker for that light, breaker #2, and proceeded to disconnect all the wires from the duplex.
After the duplex was completely disconnected, I flipped both breakers back on and used my multimeter to check the wires which had been going to the duplex. Comparing them to the grounds that were pigtailed in the box here is what I found.
Wire #1
Black wire hot(supplied by breaker #1), white not hot
Wire #2
Black not hot, white not hot
Wire #3
Black hot(supplied by breaker #2), white hot(supplied by breaker #2)
Here is what else I was able to determine. The light fixture which flickered was controlled by 3 way switches. I checked the wiring of the switches and noted the following.
Light fixture
The only wiring going to the fixture was a single romex. Black to black, white to white, ground not connected.
Switch box #1
Hot wire from breaker #2 to common terminal, neutral tied to other neutrals going elsewhere, grounds pigtailed. The black & white of a 14/2 with ground was used as the travelers from the switch. The neutral was not carried to the other switch box.
Switch box #2
This box has two switches, a SPST controlling a light on breaker #1 & the 3 way switch. The travelers from the other switch were connected to the traveler terminals, the common terminal with the the black going to the fixture. The neutral coming from the fixture was shared with the neutrals on the circuit with hot controlled by breaker #1. The neutrals were pigtailed. I undid them and checked the neutral coming from what I believe is the fixture & it was hot.
The duplex is some where between the box with the shared neutral & the breaker box. I did not trace out everything on both circuits.
So is there a problem? Is the weirdness at the duplex caused by the shared neutral? With all wires connected,at the duplex, it measures correctly, 120V H-G/H-N, 0V N-G. Everything on those two circuits works properly. Is the solution to pigtail the wires at the duplex so they cannot be disconnected from each other. The two circuits are right next to each other, on separate phases, in the box. Should their handles be tied together?
I've searched high & low for an answer on the net and haven't come across a solid answer. It seems to me that as long as everything at the duplex is connected that everything is "balanced" and there is no problem. But something just doesn't feel right to me.
Help! Thanks!
-Dave
This is kind of complicated so I'll do my best.
I was replacing an outlet powered by breaker #1. I shut off breaker #1, and confirmed the outlet had "no power" via a light. This duplex had 3 14/2 with ground wires going to it. They were not pigtailed but connected via the back stabs & side wire terminals. As I began disconnecting the neutrals, I noticed some sparks and the ceiling light in the adjacent room flickering. That light was not on the same breaker. I flipped off the breaker for that light, breaker #2, and proceeded to disconnect all the wires from the duplex.
After the duplex was completely disconnected, I flipped both breakers back on and used my multimeter to check the wires which had been going to the duplex. Comparing them to the grounds that were pigtailed in the box here is what I found.
Wire #1
Black wire hot(supplied by breaker #1), white not hot
Wire #2
Black not hot, white not hot
Wire #3
Black hot(supplied by breaker #2), white hot(supplied by breaker #2)
Here is what else I was able to determine. The light fixture which flickered was controlled by 3 way switches. I checked the wiring of the switches and noted the following.
Light fixture
The only wiring going to the fixture was a single romex. Black to black, white to white, ground not connected.
Switch box #1
Hot wire from breaker #2 to common terminal, neutral tied to other neutrals going elsewhere, grounds pigtailed. The black & white of a 14/2 with ground was used as the travelers from the switch. The neutral was not carried to the other switch box.
Switch box #2
This box has two switches, a SPST controlling a light on breaker #1 & the 3 way switch. The travelers from the other switch were connected to the traveler terminals, the common terminal with the the black going to the fixture. The neutral coming from the fixture was shared with the neutrals on the circuit with hot controlled by breaker #1. The neutrals were pigtailed. I undid them and checked the neutral coming from what I believe is the fixture & it was hot.
The duplex is some where between the box with the shared neutral & the breaker box. I did not trace out everything on both circuits.
So is there a problem? Is the weirdness at the duplex caused by the shared neutral? With all wires connected,at the duplex, it measures correctly, 120V H-G/H-N, 0V N-G. Everything on those two circuits works properly. Is the solution to pigtail the wires at the duplex so they cannot be disconnected from each other. The two circuits are right next to each other, on separate phases, in the box. Should their handles be tied together?
I've searched high & low for an answer on the net and haven't come across a solid answer. It seems to me that as long as everything at the duplex is connected that everything is "balanced" and there is no problem. But something just doesn't feel right to me.
Help! Thanks!
-Dave
