NEC 312.11 Spacing question on PDU

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steve1938

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On a PDU with an external door an internal dead front is added through which the mains breaker is operated. The internal dead front was hinged to make thermal scanning easier for a customer. Right behind the dead front is a 75KVA transformer. A glastic shield (60mils) is bolted to the back of the dead front 25KV dielectric. The transformer taps are close to the shield - about 1/4 inch away.

Engineer on site says PDU does not conform based on 312-11 A-2 which does not make sense. The dead front is 1-1/2 inches away from the cabinet exterior door as is lined with the glastic to protect the operator.

Any advice on how to resolve this?
 
Let the engineer argue with the PDU manufacturer. Personally I don't understand his complaint based on the code article you posted 312.11(A)(2).
 
Tom brings up an excellent point. A lot of electrical equipment is not built according to the NEC. How many times have you seen more than one conductor in a lug or other things prohibited by the NEC within listed equipment.
 
Thanks for reviewing and pointing me in the right direction.

90.7 does define that if the part is listed per UL standard (this case UL60950) and marked with the appropriate sticker for documentation that the "factory installed internal wiring or the construction of equipment need not be inspected at the time of installation of equipment, except to detect alterations or damage..."
 
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