# MCC Room Requirements



## Forge Boyz

In a sawmill? Just be glad you actually have a room to put the MCC in.

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## varmit

The actual room construction would be determined by local building codes. The electrical installation clearances and ingress/ egress would be determined by NEC article 110.

There are some specific NEC requirements if there are transformers located in this space. See article 450.


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## JRaef

The only thing that changes is the clearance distances when doors are open (table 110.26) based on conductivity of the wall material. Sheetrock is considered non-conductive, concrete IS considered conductive. I have, on a couple of occasions, added Sheetrock to a wall (one concrete, one corrugated steel) in order to decrease the clearances required.


The only other requirement is that MCCs are all rated for a maximum of 40C (104F) operation so the room must have adequate ventilation and/or air conditioning to be able to maintain that when everything is running. I have walked into some MCC rooms where the heat blast makes me swoon, then the users are complaining that their VFDs are continually failing "for no reason".


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