disconnect for transformers

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boatfull

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can't seem to find where a disconnect would be required on the primary side of the transformer. i know about the requirements on the secondary side of the transformer. the main for the transformer now is three floors above the transformer.
thanks
 
You can't find it because it is not there. You have to have overcurrent protection on the primary windings, the primary feeder, the secondary windings, and the secondary conductors. A single circuit breaker on the primary and one on the secondary can between them do all those jobs. But there is no requirement for a local disconnecting means.
boatfull said:
The main for the transformer now is three floors above the transformer.
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That is allowable.

 
This requirement will be modified in the 2011 NEC.

450.14 Disconnecting Means. Transformers, other than
Class 2 or Class 3 transformers, shall have a disconnecting
means located either in sight of the transformer or in
a remote location. Where located in a remote location,
the disconnecting means shall be lockable, and the location
shall be field marked on the transformer.
Click to expand...
 
Pierre C Belarge said:
This is one of the changes in the '11 that I see costing some contractor a ton of money.
Click to expand...

At first I thought that too but then I read it again. Since most disconnects are capable of being locked in the open position all the contractor would need to do is comply with the transformer labeling requirement. Not really a big thing.
 
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