Class-1 Div-2 Question

[angrymonkey]

We have a Class-1 Div-2 hazardous location with armor-clad cables feeding 277v circuits
into the classified area. The contractor installed seals on the ends of each feeder cable
landing them into JIC hinged gasketed 4X enclosure. The contractor used terminal strips
inside the junction box to splice wires going to each load in the hazardous area.
Each of the cables leaving the JIC junction/splice box has a seal as it leaves the j-box.
Contractor is claiming the application is non-arching & sparking and does not need
to be installed in an enclosure rated for the area.

I see several problems with this installation:

The enclosure is not UL listed for the application (4X enclosure)
The wires are spliced inside the junction box (gas can migrate past the seals inside the wires)
The enclosure will not contain the explosion if the gases ignite inside the j-box.
The enclosure gasketed seal will not cool the escaping gases to a safe temp in the hazardous
area if the gases inside the enclosure ignite and escape.

Anyone have an opinion be on this?

 

[petersonra]

501.10 Wiring Methods. Wiring methods shall comply with 501.10(A) or 501.10(B).

501.10(B) Class I, Division 2.
...
(4) Boxes and Fittings. Boxes and fittings shall not be
required to be explosionproof except as required by
501.105(B)(1), 501.115(B)(1), and 501.150(B)(1).

It would probably be good to review the whole of article 501 as it applies to division 2 areas.

 

[KentAT]

Doesn't appear to be a problem as long as (1) type AC armored cable is not used, (2) the enclosure only contains splices or terminals, (3) grounding and bonding requirements are met

Kent

 

[rbalex]

I confess I’m still a bit confused about the installation description. I couldn’t quite tell whether the terminal box was located in the Division 2 location or in an unclassified location just outside the Division 2 location. In either case, if the wiring method itself was acceptable in Division 2 and the comments of the two previous posts were observed, it probably didn’t need any seals at all.

Edit add: See 501.10(B) for acceptable Division 2 wiring methods.