501.10(B)(1) Terminated with Listed Fittings

[fifty60]

Regarding the requirement in NFPA 70 2017 501.10(B)(1) that type PLTC, TC, ect. cables must be terminated with listed fittings, is this regarding where the individual wires connect to the end device or is it the actual NPT fitting where the cable enters an enclosure? Would it be wherever the sheath on the cable is removed to reveal the final run of individual wires?

[petersonra]

Regarding the requirement in NFPA 70 2017 501.10(B)(1) that type PLTC, TC, ect. cables must be terminated with listed fittings, is this regarding where the individual wires connect to the end device or is it the actual NPT fitting where the cable enters an enclosure? Would it be wherever the sheath on the cable is removed to reveal the final run of individual wires?

Pretty sure they are referring to where it enters the box. It would not make much sense otherwise since there is no fitting anywhere else.

[fifty60]

That makes sense. Another related question. For example, PLTC cable, when the jacket is removed from the cable, is the exposed wiring inside the cable still PLTC rated? Or does the PLTC rating only apply to the cable with the jacketing and not the individual conductors?

[petersonra]

That makes sense. Another related question. For example, PLTC cable, when the jacket is removed from the cable, is the exposed wiring inside the cable still PLTC rated? Or does the PLTC rating only apply to the cable with the jacketing and not the individual conductors?

I don't see how it can be a PLTC cable if the jacket has been removed. They are just conductors at that point.

[fifty60]

For example, PLTC wire is acceptable wiring a Class I Div 2 location. I run my cable to my enclosure, which is also located in a Class I Div 2 location. I enter this enclosure through a listed fitting. Inside the enclosure, I will remove the jacketing on the PLTC cable, and the individual conductors will terminate at terminals on a PLC input card that is rated for Class I Div 2.

So I know the PLTC wire is acceptable, but what about the final foot of wiring in a class I div 2 location where I am inside the final enclosure and connecting the conductors to a device?

[petersonra]

For example, PLTC wire is acceptable wiring a Class I Div 2 location. I run my cable to my enclosure, which is also located in a Class I Div 2 location. I enter this enclosure through a listed fitting. Inside the enclosure, I will remove the jacketing on the PLTC cable, and the individual conductors will terminate at terminals on a PLC input card that is rated for Class I Div 2.

So I know the PLTC wire is acceptable, but what about the final foot of wiring in a class I div 2 location where I am inside the final enclosure and connecting the conductors to a device?

you are allowed to have THHN conductors in a C1D2 junction box. Why not the conductors from inside a cable?

[rbalex]

The conductors in PLTC cable aren't THHN - or any other 600V rated conductor. They are 300V, 105C.

That said, the NEC isn't a "design specification" and there is an expectation that a bit of common sense would apply. If the PLTC cables are otherwise acceptable in both Articles 500 and 725, then it is a reasonable expectation that they can be terminated in enclosures that are also acceptable in Article 500 with enough jacket removed to terminate the conductors.

[fifty60]

I am not able to find where THHN wiring is allowed inside a junction box in a CID2 location. I k now that 501.10(B)(4) says that boxes and fittings are not required to be explosion proof, but that does not seem to provide the justification of general purpose enclosures with THHN wiring..

[Jim1959]

I am not able to find where THHN wiring is allowed inside a junction box in a CID2 location. I k now that 501.10(B)(4) says that boxes and fittings are not required to be explosion proof, but that does not seem to provide the justification of general purpose enclosures with THHN wiring..

I believe any wiring type would be allowed inside an approved raceway or enclosure, the difference with PLTC or TC cable is that it can be installed exposed on a cable tray, therefore it has to be approved for the classification.

[fifty60]

Would the justification for this be 501.10(B)(1)(2) "Enclosed gasketed busways and enclosed gasketed wireways."?