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#30845 - 10/29/03 07:43 PM Power problem
Whitey Offline
Junior Member
Registered: 10/01/03
Posts: 4
Loc: South Baptiste,Alberta,Canada
Maybe someone has run across this before,i was called to check some plugs in a school recently,the complaint was a fried microwave oven and computers,i tested the voltage at the plugs and it was 180V between neutral and the hot wire,also 117V between neutral and ground.There were 8 wires leaving the panel in emt feeding aprox 20 plugs,6 hots 2 neutrals,service to school is 3phase 4wire.It appears only one of the circuits was affected,a red circuit,i turned the breaker off one at a time until problem cleared,it appears a black circuit was causing the problem and the voltage returned to normal on the affected circuit.Is this a possible open neutral problem? any responses are appreciated.
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#30846 - 10/30/03 02:01 AM Re: Power problem
Scott35 Offline

Broom Pusher and
Member
Registered: 10/19/00
Posts: 2707
Loc: Anaheim, CA. USA
Sounds like maybe you have a 4 wire Delta system here!?
180-208 VAC from L-C would be found on one ungrounded conductor (typically ØB).

If not, look for open noodle situation on that branch circuit, or possibly on the Subfeed.

Scott35
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#30847 - 10/30/03 05:41 PM Re: Power problem
Active 1 Offline
Member
Registered: 02/22/03
Posts: 687
Loc: Grayslake IL, USA
A problem with the panel or transformer bonding the nutral to ground?
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#30848 - 10/31/03 07:10 AM Re: Power problem
Whitey Offline
Junior Member
Registered: 10/01/03
Posts: 4
Loc: South Baptiste,Alberta,Canada
Just an update,turns out the problem was a neutral splice in a device box that was not twisted in the wirenut properly, intermittently under a heavy load, i believe it would arc and open circuit.
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