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#166548 - 07/23/07 01:04 PM Burned Switch
renosteinke Offline
Cat Servant
Member

Registered: 01/22/05
Posts: 5299
Loc: Blue Collar Country
Picture submitted by Waymag. He'll fill in the details:



Edited by renosteinke (07/24/07 04:28 PM)

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#166568 - 07/23/07 04:53 PM Re: Burned Switch [Re: renosteinke]
ShockMe77 Offline
Member

Registered: 06/11/05
Posts: 823
Loc: Rahway, New Jersey
Lightning?

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#166570 - 07/23/07 05:26 PM Re: Burned Switch [Re: ShockMe77]
waymag Offline
Member

Registered: 01/13/02
Posts: 68
Loc: dallas, texas, USA
We still do not know what made this switch have a melt down. It was on a 277volt circuit and the breaker never tripped. The breaker was a Cutler Hammer Power Line c style breaker. This is also a code violation type deal because 120 and 277 were in the same box. I know the contacts inside the switch had welded together.

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#166573 - 07/23/07 05:40 PM Re: Burned Switch [Re: waymag]
electure Offline

Member

Registered: 12/24/00
Posts: 4225
Loc: Fullerton, CA USA
The 120V switch and 277V switch can be in the same box IF the voltage between 2 adjacent switches doesn't exceed 300V.

It's in 404.8(B) \:\)

(I wonder what the voltage between the 2 systems is?)

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#166579 - 07/23/07 06:21 PM Re: Burned Switch [Re: electure]
renosteinke Offline
Cat Servant
Member

Registered: 01/22/05
Posts: 5299
Loc: Blue Collar Country
Perhaps the switch was not rated for 277?

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#166601 - 07/24/07 07:45 AM Re: Burned Switch [Re: electure]
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
 Originally Posted By: electure
(I wonder what the voltage between the 2 systems is?)


Best case = 157V, worst case = 397V, depending upon phasing.

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#166626 - 07/24/07 05:55 PM Re: Burned Switch [Re: pauluk]
electure Offline

Member

Registered: 12/24/00
Posts: 4225
Loc: Fullerton, CA USA
My, how simple! \:D

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#166627 - 07/24/07 06:12 PM Re: Burned Switch [Re: electure]
waymag Offline
Member

Registered: 01/13/02
Posts: 68
Loc: dallas, texas, USA
Well it had 120v and basically 480v too because the other 2 switches were 277 on a phase and 277 on b phase... 1-120v switch and 2-277 volt switches...after repullint wire back up to j box I did an amp reading and got 4 amps on the 120v switch 3.5 on one of the 277 volt switches and 1.5 on the other 277 volt switch.

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