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Joined: Jun 2015
Posts: 2
D
DAB Offline OP
New Member
I am the owner's representative for the construction of a vehicle maintenance facility. This facility has monitoring of CO and NO2 levels. If a threshold level is met, an exhaust fan comes on and a fresh air wall louver is opened.

The electrical contract installed a bank of four starters along a wall for these exhaust fans. He brought in the line side conductors, from four separate breakers, into one enclosure and then fed the conductors through nipples in the sides on the enclosures to the other three starters. Same for load side to fans. These starters are three phase 208V. He jumpered a ground from enclosure to enclosure.

Apart from being a "cheesy" installation (in my opinion), this does not appear to violate 312.8. Since the conductors pass through the enclosures, does the starter still need to have a warning label that separate power sources are present?

Is there another section in the code that would prevent such a lazy installation? My concern is that if we have a problem, or flash event, in one starter, we could lose several other starters that are needed for life safety equipment.

Thank you for any help you can give me.

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Joined: Apr 2002
Posts: 7,381
Likes: 7
Member
From what you describe, it appears to be compliant. However there may be an issue with fill capacity.

As to a label, IF you are under the 2011 NEC (312.8 (3)) a warning label as to the location of the means of disconnect for ALL the conductors must be posted.

Based on the (3) verbiage, said label will indicate that multiple sources of power are present, although another label stating 'multiple sources' would be a prudent item.

As to the quality of the workmanship.....here in NJ, I cannot fail for that; however there may be other things upon performing a compliance inspection.

Reading your last comment regarding that this is a 'life safety system, yes a flash incident will be a problem.

Was this a designed plan job, or a seat of the pants job??


John
Joined: Jan 2005
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Cat Servant
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I thought there was something in 450, restricting the use of starter enclosures as raceways?

Joined: Apr 2002
Posts: 7,381
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Reno:
I didn't see anything in a quick read of 430. Not saying there may or may not be something buried in there.



John
Joined: Jun 2015
Posts: 2
D
DAB Offline OP
New Member
John,

It was an engineered project. A public project. While my experience has mostly been on private projects where engineering is a little more detailed, the design of public projects have a little more ambiguity to them to account for flexibility with different manufactured components (i.e. the exhaust fans). Sole sourcing is an issue with public projects and generally the lowest "responsible" bidder must be used.

Thank you for your help.


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