Class 1 Div 1

[paradis]

501-4 states that rigid nonmetallic conduit can be used when buried 24" below grade and covered by 2" of concrete. Then goes on to say it can be omitted where subject to provisions of 511-4 Ex.Does this apply to an installation in a sewage pump station from the wetwell to the pump control panel?

 

[sc57ford]

Re: Class 1 Div 1

I'm sorry, but your question does not have all the necessary information. Has an Area Classification drawing been completed? From that you will know where the Class 1, Div. 1 boundary location ends. You will need to seal the rigid steel conduit in the Class 1, Div 1 area within 18 inches of the boundary as you leave the classified area. Your underground rigid non-metallic conduit must be 24 inches below grade and concrete encased. A rigid metal conduit must be used where exiting the ground on both ends, and depending on your Area Classification, may need another seal.

 

[wolfman56]

Re: Class 1 Div 1

I've done 2 of these in the last year, from what I remember, the hazardous area is only inside the tank. The way I did the installation was the most economical parts wise. For the intriscally safe wiring, use plastic j-box inside tank, and plastic cord connectors, then from there run PVC to control panel normal burial, use duct seal at the panel. For the pump feeds, run a 1" RMC about 12" long passing from the tank, to a seal-off fitting, after the fitting mount a plastic j-box, run the pump wires thru the seal-off and splice in j-box, then from there run PVC to control panel normal burial. And always use water proof wire nuts.