UNION BEFORE THE SEALING CABLE GLAND 1

[nightfox1925]

I have seen an installation involving cables directly connected to an explosion proof enclosure via sealing type cable glands. I observed however in one occasion that there is a union between the sealing type cable gland and the explosion proof enclosure. Is this a Code violation?

I thought that the NEC does not allow any union between the enclosure and the sealing type cable gland. Further, the union may pose as a point of failure since it may create passage of combustible gas into the enclosure in the event of failure due to..say corrosion. Is there any code reference that allows this? I ask the maintenance people and they say that this union is required during maintenance works.

GO PLACIDLY, AMIDST THE NOISE AND HASTE-Desiderata

 

[waross]

I believe there are explosion proof unions available.
respectfully

 

[resqcapt19]

The NEC does not permit any fittings between a seal and a boundry point, but explosionpoof fittings are permitted between a seal and explosionproof enclosures.

501.15(A)(1) ... Conduit seals shall be installed within 450 mm (18 in.) from the enclosure. Only explosionproof unions, couplings, reducers, elbows, capped elbows, and conduit bodies similar to L, T, and Cross types that are not larger than the trade size of the conduit shall be permitted between the sealing fitting and the explosionproof enclosure.

501.15(A)(4) ... Except for listed explosionproof reducers at the conduit seal, there shall be no union, coupling, box, or fitting between the conduit seal and the point at which the conduit leaves the Division 1 location.

Don

 

[nightfox1925]

Thanks Don, Waross.

GO PLACIDLY, AMIDST THE NOISE AND HASTE-Desiderata