75 KVA Transformer/ Suspended Ceiling

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jamesoftn

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Q4. What are the requirements in locating transformers above a suspended ceiling?
A4. Dry-type transformers, rated not more than 50 kVA, are permitted above suspended ceilings or in hollow spaces of buildings, if not permanently closed in by the structure [450.13(B)]. Dry-type transformers not exceeding 50 kVA with a metal enclosure can be installed above a suspended ceiling space used for environmental air-handling purposes [300.22(C)(2)].

Per the question and answer newsletter; It appears from the answer that a 75KVA transformer cannot be installed above a suspended celing. 450.13 B says permanently closed in by structure. The removeable ceiling tiles are accessible or are they permanent So is a transformer allowed to be installed above a suspended ceiling
 
To me, 450.13 could be a bit clearer, but it appears it appears that unless they are in the open or 50kva or less, they must be readily accessible
 
it may be an amendment in NYC...they allow things due to space constraints...but in NJ it is a no go....as per the NEC
 
augie47 said:
Since I am one, I guess so.:)
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I absolutely meant nothing personal or meant no offense at all.

What I meant was,,,,,,when an inspection takes place, and the inspector passes it, it does not mean there are no code violations on the job. It means the inspector did not SEE any code violations. It does not mean there are none.
 
mcclary's electrical said:
I absolutely meant nothing personal or meant no offense at all.

What I meant was,,,,,,when an inspection takes place, and the inspector passes it, it does not mean there are no code violations on the job. It means the inspector did not SEE any code violations. It does not mean there are none.
Click to expand...

no offense at all... my answer was in jest...
 
450.13 Accessibility.
All transformers and transformer vaults shall be readily accessible to qualified personnel for inspection and maintenance or shall meet the requirements of 450.13(A) or 450.13(B).
(A) Open Installations. Dry-type transformers 600 volts, nominal, or less, located in the open on walls, columns, or structures, shall not be required to be readily accessible.
(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). Transformers so installed shall not be required to be readily accessible. No NYC amendments on it
 
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