72 Pole Panel with a main breaker

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shroominator

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I have a design with a 120/208V, 3PH, 4W, 72-pole, 225A panelboard with a 225A main breaker on the secondary side of a 75KVA transformer. A question has come up regarding the maximum number of poles allowed in this panel on the basis of Article 408.36 (Exception 2), limiting this panel to 42-poles because of the 3-pole main breaker. I do not think this applies at all. I believe they are just misinterpreting the definition of 2 or 3 pole breakers counting as 2 or 3 overcurrent devices.

I appreciate all comments.
 
To me the exception applies to panel such as the older "split buss" type and what you have is Code compliant.
 
shroominator said:
I have a design with a 120/208V, 3PH, 4W, 72-pole, 225A panelboard with a 225A main breaker on the secondary side of a 75KVA transformer. A question has come up regarding the maximum number of poles allowed in this panel on the basis of Article 408.36 (Exception 2), limiting this panel to 42-poles because of the 3-pole main breaker. I do not think this applies at all. I believe they are just misinterpreting the definition of 2 or 3 pole breakers counting as 2 or 3 overcurrent devices.

I appreciate all comments.
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I think each individual OC device counts. a 3 pole is 3 OC devices.

In any case, the article cited does not limit the number of OC devices in a PB, it only allows some fudging on the PB OCPD if you have 42 or fewer OC devices.
 
shroominator said:
Is it within code to have a 3-pole main on a 72-pole panelboard? I think so, or why remove the 42-pole limit at all.
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That makes sense to me ,if the 42 circuit limitation has been removed then Exception 2 doesn't apply or maybe it should have been removed too.

dick
 
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