480 volt step down transformer Disconnect

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Fordean

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New Jersey
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Electrical Contractor
Installing a 480 to 120/208 step down transformer. 75 KVA Wall mount.
Their is a block wall in between the 480 service and the Location of the 75 kva transformer.
From the transformer. Will be feeding 208 volt Main breaker load center.
Question is the Disconnect on the Line side. Can it be on other is of wall or does the Line of sight come to play.
Breaker from 480 service will be the fused line.
 

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Not required to be within sight if the transformer is labeled with the location of the primary disconnect.
 
Fordean said:
Installing a 480 to 120/208 step down transformer. 75 KVA Wall mount.
Their is a block wall in between the 480 service and the Location of the 75 kva transformer.
From the transformer. Will be feeding 208 volt Main breaker load center.
Question is the Disconnect on the Line side. Can it be on other is of wall or does the Line of sight come to play.
Breaker from 480 service will be the fused line.
Click to expand...
Remember the transfomer secondary conductor rule 240.21 (C) (2), conductor length without protection 10' max. between the transformer and the OCPD and need to comply with 240.21 (C) (2) (1). Your drawing does not show conductor length.
 
LibertyEngineering said:
Remember the transfomer secondary conductor rule 240.21 (C) (2), conductor length without protection 10' max. between the transformer and the OCPD and need to comply with 240.21 (C) (2) (1). Your drawing does not show conductor length.
Click to expand...
Why not 25'
 
infinity said:
Why not 25'
Click to expand...
Well as long as it complies with 240.21 (C) (3) sure. Not enough in OP to determine if it would comply. Industrial installation?, also it says 'For the supply of switchgear or switchboards....... OP indicates it is feeding a load center. Also would need to comply with (1) thru (4).

But yes absolutely can be 25' in that case.
I do question the 'For the supply of switchgear or switchboards' portion though. Does a load center qualify as a switchboard by definition in NEC?
 
LibertyEngineering said:
Well as long as it complies with 240.21 (C) (3) sure. Not enough in OP to determine if it would comply. Industrial installation?, also it says 'For the supply of switchgear or switchboards....... OP indicates it is feeding a load center. Also would need to comply with (1) thru (4).

But yes absolutely can be 25' in that case.
I do question the 'For the supply of switchgear or switchboards' portion though. Does a load center qualify as a switchboard by definition in NEC?
Click to expand...
240.21(C)(6) doesn't have any of those requirements.
 
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