# First point of disconnect above drop ceiling?



## nyerinfl (Dec 1, 2007)

Any issue with putting the first point of an interior disconnect on a commercial application above a drop ceiling?

Scenario; Tenant improvement project, the building supply is 480, fed from an exterior meter stack with a main breaker. There is no room for the transformer below the ceiling, so it is going to be suspended above the grid, with the 480 volt disconnect mounted on the transformer. There are no 277 or 480 volt loads in the space so there is no need for a 480 panel, making the first interior shutoff the disconnect at the suspension transformer.

Any problems here?


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## sbrn33 (Mar 15, 2007)

Above 6'10"?


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## Awg-Dawg (Jan 23, 2007)

Depending on the size of the XFMR, you wont be able to put it above the ceiling.


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## McClary’s Electrical (Feb 21, 2009)

The measurement is 6'7" but does not apply here. That disco could be as high as you want it. If the xfmr is bigger than 50 kva you cannot put it above that ceiling.


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## nyerinfl (Dec 1, 2007)

sbrn33 said:


> Above 6'10"?


If you're referring to 404.8(A) for 6' 7" I would take exception 2 into consideration which allows it to be set higher to disconnect the equipment which it serves. Not sure if this rule would apply here?


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## nyerinfl (Dec 1, 2007)

mcclary's electrical said:


> If the xfmr is bigger than 50 kva you cannot put it above that ceiling.


Code ref please?


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## McClary’s Electrical (Feb 21, 2009)

nyerinfl said:


> Code ref please?


 

*450.13 (B) Hollow Space Installations.​*​​​​Dry-type transformers
600 volts, nominal, or less and not exceeding 50 kVA shall
be permitted in hollow spaces of buildings not permanently
closed in by structure, provided they meet the ventilation
requirements of 450.9 and separation from combustible materials​
requirements of 450.21(A)


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## Awg-Dawg (Jan 23, 2007)

mcclary's electrical said:


> If the xfmr is bigger than 50 kva you cannot put it above that ceiling.


 
Ive hung them high and had the ceiling guys "box" around them.


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## sbrn33 (Mar 15, 2007)

I believe he is talking about the service disconnect? OH and did it used to be 6'10"?

nevermind reread


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## Dennis Alwon (May 9, 2009)

I would read 110.26


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## mbednarik (Oct 10, 2011)

Is there a main in the meter stack? If it is the main disconnecting means it needed to be readily accessible.


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## TGGT (Oct 28, 2012)

Dennis Alwon said:


> I would read 110.26


Are you concerned about the 3 foot clearance?


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## Dennis Alwon (May 9, 2009)

TGGT said:


> Are you concerned about the 3 foot clearance?


Among all the other distances as well as readily accessible, etc


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## TGGT (Oct 28, 2012)

Dennis Alwon said:


> Among all the other distances as well as readily accessible, etc


Only as far as the first means of disconnect is concerned?


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## McClary’s Electrical (Feb 21, 2009)

TGGT said:


> Only as far as the first means of disconnect is concerned?


Any disconnect


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