GFCI's and current imbalance

[kwired]

You are correct of course; if the neutral were to get separated from the POCO neutral and still be connected to ground the branch voltages would still wander. Usually when the neutral gets disconnected it gets separated from both the POCO neutral and the ground, though it is the separation from POCO neutral that causes the problem. I don't know what I was thinking.

Depends where it is separated and what other alternate paths are available. If a low enough alternate path is available you may not even know the neutral is open, because in a way it is not open.

 

[Eddy Current]

They had better be the same (120V), or two wire 120V loads are going to either be starved for voltage or exposed to overvoltage. This happens, BTW, if and when the neutral gets separated from ground at the service; in that case the leg voltages do sum to 240 but can vary according to what loads are on which leg(s). Bonding the neutral to ground keeps it from happening.

I have a question what exactly is happening when say for example you separate the neutral in a junction box but the hots are still tied together. How come the neutral hurts worse sometimes than the hots if its just carrying the unbalanced load.

 

[ActionDave]

I have a question what exactly is happening when say for example you separate the neutral in a junction box but the hots are still tied together. How come the neutral hurts worse sometimes than the hots if its just carrying the unbalanced load.

http://forums.mikeholt.com/showthread.php?t=89023&p=708650#post708650This links to a post I saved from a great member of this forum. I think it will be helpful even though it is about services more than MWBC's. But since the service is nothing more than one big MWBC I think it might help.

 

[ptonsparky]

I have a question what exactly is happening when say for example you separate the neutral in a junction box but the hots are still tied together. How come the neutral hurts worse sometimes than the hots if its just carrying the unbalanced load.

1.....quit working it hot.


2.....stop working it hot

 

[kwired]

I have a question what exactly is happening when say for example you separate the neutral in a junction box but the hots are still tied together. How come the neutral hurts worse sometimes than the hots if its just carrying the unbalanced load.

Hurts worse is probably more in the mind than anything. For one thing you are touching something you didn't expect to bite you so it may seem worse just because of that. In a basic two wire circuit if you open the neutral you still have full applied voltage across the opened conductor as it is no different than having an open switch in that portion of the conductor.

 

[ptonsparky]

I have a question what exactly is happening when say for example you separate the neutral in a junction box but the hots are still tied together. How come the neutral hurts worse sometimes than the hots if its just carrying the unbalanced load.

This is certainly in the appropriate Forum section.