Class 1 Div 2 terminal box requirements 1

[ControlEE]

I have an application where a piece of equipment will be taken down and re-assembled repeatedly in Class 1 Div 2 locations. It will have 480/3/60 motor circuits and 120/1/60 control circuits. All of the motor controls will be located in enclosures rated for Class 1 Div 1, and all points of entry into and out of these enclosures will have seal fittings. Wires coming out of the elcosures will be routed in rigid conduit. At points where the equipment will be dis-assembled I will need junction boxes. Would junction boxes with only terminal strips for the motor and control circuits be required to be explosion-proof as well, or are Nema 4 and 4X boxes permitted? Please respond with a good reference.

 

[JLSeagull]

As I interpret NFPA 70-2008, if the junction box is only terminations and lacks any arcing contacts, heat producing components or have exposed surface near 80% of the ignition temperature; then a general purpose NEMA 4 enclosure is suitable. Locate the main motor termination enclosure within 1.8 m of the motor. (430.245 (B)).

See wiring methods 501.10 (B)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)." The sections cited apply to the contacts etc. Use rigid or intermediate conduit with bonding locknuts and bushings.