Class II Division 2
- Thread starter DAWGS
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Thanks.
- Location
- Mission Viejo, CA
- Occupation
- Professional Electrical Engineer
What is the Group?
Not sure? It is a rail car coal dumping station at apower plant.
- Location
- Mission Viejo, CA
- Occupation
- Professional Electrical Engineer
It's probably Group F - I just wanted to make sure it wasn't "E."
The only restriction for Class II, Division 2, Group F would be that the wireway is dusttight [502.10(B)(1)(2) & 502.10(B)(4)] ] and otherwise suitable for the location (indoor/outdoor) and making splices in it. Threaded bosses are a requirement in Division 1.[502.10(A)(4)]
The "Big Issue" in Class II is actually good housekeeping. In Division 2 there's a pretty broad array of acceptable wiring methods if the location is kept in good order.
P.S. Make sure it gets properly documented [500.4(A)]
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- Location
- Mission Viejo, CA
- Occupation
- Professional Electrical Engineer
As I did in my original response to the OP, I ask, "What is the Group?" Group E is automatically Division 1 and full threaded connections (enclosure bosses) are necessary both for grounding/bonding, and potential enclosure explosion integrity.
For other Groups, usually, I often see a tendency to overclassify Class II; but a valid Class II, Division 1 still needs bosses as you noted.
As a side comment, I tend to agree that bosses may be a bit of overkill for Group G if proper grounding/bonding is applied, since heat build up becomes a more prevalent concern in Division 1.
In all three Groups, E, F & G, good housekeeping is the best overall option, if at all possible.
For other Groups, usually, I often see a tendency to overclassify Class II; but a valid Class II, Division 1 still needs bosses as you noted.
As a side comment, I tend to agree that bosses may be a bit of overkill for Group G if proper grounding/bonding is applied, since heat build up becomes a more prevalent concern in Division 1.
In all three Groups, E, F & G, good housekeeping is the best overall option, if at all possible.
Coal dust...
Coal dust...
Utility generating plants are exempt from NEC. I would think that the area would be Division 1. Coal dust in a railcar dumping operation will be explosive if suspended in air...same as grain elevators. I would use hubs and bond every part that I could to eliminate spark potential. Might want to check the utility specs and the NESC which would be applicable...
Coal dust...
Utility generating plants are exempt from NEC. I would think that the area would be Division 1. Coal dust in a railcar dumping operation will be explosive if suspended in air...same as grain elevators. I would use hubs and bond every part that I could to eliminate spark potential. Might want to check the utility specs and the NESC which would be applicable...
- Location
- Mission Viejo, CA
- Occupation
- Professional Electrical Engineer
While utilities are exempt from the NEC, they still follow the same laws of physics.
As I said, there is a tendency to over-classify Groups F and G. It is especially difficult to create a Class II, Division 1, Group F or G location - even if you try to. I offer NFPA 499 Appendix A, Section A5.2.2 for some explanatory reading. Nothing in the NESC Rule 127A changes that opinion.
As I said, there is a tendency to over-classify Groups F and G. It is especially difficult to create a Class II, Division 1, Group F or G location - even if you try to. I offer NFPA 499 Appendix A, Section A5.2.2 for some explanatory reading. Nothing in the NESC Rule 127A changes that opinion.
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