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#124791 - 12/16/06 08:36 PM Floating Neutral
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 Quote:
College campus in DC. This defines "floating" neutral. Will be fixed next week.

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#124792 - 12/18/06 01:08 PM Re: Floating Neutral
Trumpy Offline

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Registered: 07/05/02
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Wow!,
I don't like the look of this at all.
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#124793 - 12/18/06 01:42 PM Re: Floating Neutral
Luketrician Offline
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Registered: 07/08/06
Posts: 273
Loc: Sale Creek, TN USA
???? Whaa?????
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#124794 - 12/18/06 06:37 PM Re: Floating Neutral
mxslick Offline
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Registered: 10/24/04
Posts: 785
Loc: Atomic City, ID USA
I'm having a bit of trouble getting a grip on this....in pic#1 , on the right side, the silver tab behind the neutral bus..it that a line lug? Or the support post for the deadfront?

And if not, if it is as I think it appears to be, just the support for the neutral bus, why didn't the OP simply put a nut driver on the screws on the spot and fix it? I don't mean to be rude and I hope no one takes what I just said that way, but I think something's missing in the info on this one...

I do agree that it is indeed a big problem though, that floating bus will eventually get in trouble...

[This message has been edited by mxslick (edited 12-18-2006).]
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#124795 - 12/20/06 01:40 AM Re: Floating Neutral
e57 Offline
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Registered: 05/27/03
Posts: 2837
Loc: S.F.,CA USA
From the appearance of the treads on the screws thay dont seem to be an \electrical connection -just the neutral bar dangling there. (Physicaly Floating)
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#124796 - 12/20/06 03:26 AM Re: Floating Neutral
RODALCO Offline
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Registered: 12/08/05
Posts: 863
Loc: Titirangi, Akld, New Zealand
If this is a 120 / 240 V supply the risk exists of overvoltages on the lighter loaded circuits when the load on the two phases is unbalanced.

Why couldn't it get fixed immidiately even with a temporary jumper to the mains POCO neutral ?
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#124797 - 12/20/06 05:11 AM Re: Floating Neutral
NORCAL Offline
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Registered: 09/25/02
Posts: 807
There is a AL neutral visable in both pics. so the neutral bar is just dangling but "functioning".

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#124798 - 12/20/06 03:35 PM Re: Floating Neutral
VAElec Offline
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Registered: 07/26/05
Posts: 48
Loc: Sterling, Virginia, US
Ok, this is Gould/ITE panel installed in '79. The silver tab behind is a plastic mount/isolater with the plastic threads stripped out. That is why it could not be bolted back with the existing hardware. Now that the semester is over the panel will be de-energized and everything bolted and nutted back in place.

The neutral bar is indeed floating and functioning. It was also in direct contact with the dead front so if the paint was to wear off there would a parallel bond in violation of NEC (250.30 I think).

[This message has been edited by VAElec (edited 12-21-2006).]
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#124799 - 12/20/06 09:54 PM Re: Floating Neutral
mxslick Offline
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Registered: 10/24/04
Posts: 785
Loc: Atomic City, ID USA
VAelec:

Thank you for the explanation. It now makes perfect sense to me.

From the pics it was hard to tell that the plastic was part of the support and isolation of the bus, and thank you for understanding that my question wasn't meant to offend.
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