Use of black pipe as conduit

[jetlag]

black pipe

black pipe

Ive seen some old commercial bldgs that used black pipe for conduit . It had a stamped marking on the end saying "greenfield conduit" and some did have a greenish color but some was black. The buildings I remember were prob built in the 30's or 40 's . I remember am old electrician telling me once the greenfied can be used any place where rmc galvanized can be used. I wonder what the old code books said about that. If that fitting has been there long enough it is probably greenfield conduit and was allowed at the time. There now, you've won your case.

 

[jetlag]

more info

more info

I appreciate all of the responses but does anyone know of chapter/verse I can use in defense of this installation.

I forgot to say in my other post but the green or black color was also inside the conduit . It also had a clear hard finish over the base color . The greenfield conduit was quite different than black plumbing pipe, It was not coated inside and didnt have the hard outer coating

 

[tom baker]

To determine the wiring rules you first determine what type of circuit this is. Look at the power supply, and review Art 725 - yes its complicated - and use the amps & volts to determine
It may be Art 725 Class 2.
The way Art 725 works, only the rules in chapter 3 apply if referenced in 725. Mostly, for Class 2 circuits, conduit or similar is not required.
Also take a look at 90.3

 

[mjolnir]

RTD Process end

RTD Process end

The side of the RTD with RTD sheath sticking out is the process side. Thermowell or not it isnt governered by the NEC if there is a code requirement it has to be from the process side not the electrical at that point.