Nonincendive Wiring passthrough for Class I Div II 1

[pgarzon]

I'm designing an enclosure to meet Class I Division II UL requirements. I have 48 cables from 4-20mAmp sensors and thermocouple, rtd, etc. The UL engineer told me that cable glands are not allowed under Class I Division II. So I have not been able to find anything that can allow me to get this cables through. Does anyone has done this before? And can share some light?

 

[waross]

Explosion proof glands are available.
Also you may be allowed to use a Meyers hub on the outside of the enclosure, with a seal fitting on the outside of the hub and a cable gland.

I have seen a lot of cables connected to instruments in classified areas with a gland connector into a sealing fitting. The sealing fitting is connected to the instrument with an explosion proof union. The cable may then be removed to change out an instrument without disturbing the seal.
The cables are HL (hazardous location) rated.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[moltenmetal]

If you're talking about passing wires from a Class 1 Div 2 area into a nonclassified (general purpose) area, you don't need explosion proof seals. Duct seals are available which can be packed with non-hardening putty- that makes pulling new wires later a lot easier than if you'd poured XP sealing compound.

If your enclosure is inside the Div 2 area, either a) everything inside it must be nonincendive (i.e. rated for Cl 1 Div 2) OR you must pressurize the enclosure with clean air or inert gas per NFPA 496. Seals to permit pressurization are also available- generally those wire glands need to seal quite a bit tighter than you can manage with duct seal putty or else you'll waste a lot of pressurizing air/nitrogen.