MV Cable in Class 1 Div 2 Location

[srsmith]

Can you use 4" liquid tight flex conduit for MV cable in a class 1 Div 2 location?
With a conduit seal on the motor terminal box and one above the concrete in
which it enters the classified area.

 

[Smart $]

Can you use 4" liquid tight flex conduit for MV cable in a class 1 Div 2 location?

Yes. 501.10(B)(2)(3) or (4)

With a conduit seal on the motor terminal box and one above the concrete in which it enters the classified area.

Hmm... I was thinking you may be able to get by with one seal, then I thought the LFMC/LNMC would mandate two, but I can find no such requirement. Using one would be dependent on distance from enclosure to CID2-unclassified boundry being max of 11' 6" (18" enclosure to seal... 10' seal to boundry) as the conduit runs and also subject to the no-fitting requirement.

 

[rbalex]

...Hmm... I was thinking you may be able to get by with one seal, then I thought the LFMC/LNMC would mandate two, but I can find no such requirement. Using one would be dependent on distance from enclosure to CID2-unclassified boundry being max of 11' 6" (18" enclosure to seal... 10' seal to boundry) as the conduit runs and also subject to the no-fitting requirement.

He only needs one seal at the boundary. There is no need for a seal at the motor terminal box since it isn't required to be explosionproof.