Shared grounded conductor two rooms?

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hockeyoligist2

hockeyoligist2

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close to greenville sc
Office kitchen, all receptacles on one circuit. A microwave and a coffee pot on a portable microwave cart, plugged in to a regular wall receptacle. Another coffee pot on the counter and a toaster grill. When they turn on the toaster (12 amp) the breaker trips.

I checked the breaker box and found the contractor had pulled in a spare set of wires in case they decided to install a garbage disposal. So I removed one of the counter receptacles, found the wires and proceeded to put them on the separate circuit. When I separated the grounded conductors I saw a spark and heard something stop running in the next room. It was the ice maker which is on another circuit.

Do I need to pull in another grounded conductor for the ice machine in the separate room?
 
When you say grounded conductors do you mean neutral or ground? White or bare?
 
hockeyoligist2 said:
Office kitchen, all receptacles on one circuit. A microwave and a coffee pot on a portable microwave cart, plugged in to a regular wall receptacle. Another coffee pot on the counter and a toaster grill. When they turn on the toaster (12 amp) the breaker trips.

I checked the breaker box and found the contractor had pulled in a spare set of wires in case they decided to install a garbage disposal. So I removed one of the counter receptacles, found the wires and proceeded to put them on the separate circuit. When I separated the grounded conductors I saw a spark and heard something stop running in the next room. It was the ice maker which is on another circuit.

Do I need to pull in another grounded conductor for the ice machine in the separate room?
Click to expand...

Yes, It seems you already have 2 circuits on one neutral. Unless this is a 3 phase panel then no, your good to go. You said the contractor pulled a "SET" of wires. What did he pull? A set for a GD to me would be hot and neutral.
 
sounds like you opened the neutral in a MWBC without turning all the circuits off. hopefully you didnt blow anything up....
 
Another concern to me, is safety, with the grounded conductor serving another room! I turned off the breakers that were labeled for that room. I checked the "hots" with my meter and used my "magic wand" to make sure everything was dead in the box.

What if I had been grounded and touching the bare wire when I pulled apart the GC? Ouch or worse!
 
hockeyoligist2 said:
Another concern to me, is safety, with the grounded conductor serving another room! I turned off the breakers that were labeled for that room. I checked the "hots" with my meter and used my "magic wand" to make sure everything was dead in the box.

What if I had been grounded and touching the bare wire when I pulled apart the GC? Ouch or worse!
Click to expand...

Grounded conductors (Neutral) can supply and number of rooms. One circuit can serve more than one room. NEVER trust you life to a label
 
hockeyoligist2 said:
Another concern to me, is safety, with the grounded conductor serving another room! I turned off the breakers that were labeled for that room. I checked the "hots" with my meter and used my "magic wand" to make sure everything was dead in the box.
Click to expand...

If all of the hots in the box were dead, and you had a neutral carrying current, then you have some circuit tracing to do. If I understand this correctly, you have hots not in your box feeding a load and the return path is through a neutral in your box. That's a no no (but you knew that).
 
Ut oh.


Don't open MWBC neutrals hot.

I learned this the easy way a long time ago. I know a few people that learned it the hard, smokey way.
 
How many (and what color) conductors were in the panel going into the conduit when you started? I've heard about

- spare hot
- spare neutral
- Kitchen circuit
- Kitchen neutral

If you shut off the kitchen circuit, then there should not have been an issue unless there was a neutral being stolen from this circuit, or there was another ungrounded conductor in the conduit. Which is it?
 
sounds like some one could have tied all the neutral conductors together somewhere....two seperate circuits that HAD their own neutrals?
 
Found it.

Found it.

I finally got a chance to spend some time on the problem this morning. After pulling out 4 receptacles I found one with the circuit going to the ice machine. Someone had tied the neutral to the receptacle instead of the one pulled for it. The lighting circuit passing though the box had 2 neutrals (back to the panel) tied in to it. All of the wires were clearly numbered for the breaker they were associated with. It must have gotten wired on a Monday morning or a Friday evening @ Beer thirty! ;)
 
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