NEMA RATED ENCLOSURE

[HenryA]

We are possibly expanding our existing walk in refrigerator by removing a wall and building it out to add space .When that happens the panelboard which supplies the evaporators and compressors would now be part of the inside of the box. I was not able to find anything on if a standard Nema 1 panelboard is acceptable in a case like that or if we would have to change it out to a Nema 3r or greater. Or is that panel able to be located in that environment at all. The temperature inside the box is between 36 and 46 degrees. any help is appreciated. thank you

 

[jap]

I would make every effort to keep the panelboard outside of the refrigerated area.

To me a 3r or greater panelboard is designed to prevent moisture from entering the enclosure from the
outside.

Problem is in this circumstance is that the heat inside the panel from the loads combined with the cool
air on the outside of the enclosure would produce moisture on the inside of the panelboard regardless
of its rating.

but thats just my two cents worth.

 

[ActionDave]

I could see good reason to keep the panel out of the walk in. The biggest one being maintaining work space.

I have seen regular type 1 panels in coolers and as strange as it may seem they do fine. Don't know about any rules either way.

 

[masterinbama]

The problem comes from air moving through conduits or cables from outside to inside or visa versa.

 

[ActionDave]

That's just it. There is no signs of condensation any where. This may be partly because the climate where I live is dry.