voltage rating for cord

[jimmytee]

Hi all, my first post. In article 400 Junior hard service cord- the "SJ" cords, is the 300V rating phase to phase or is it phase to ground?

Thank you.

 

[jumper]

Either, it is the maximum voltage that could be applied.

300V cord could be used for 240V L-L or 277 L-N, but not 480V L-L which is 277V L-N also.

 

[jimmytee]

Thank you. Could you tell me where I missed in the N.E.C. 70?

 

[ActionDave]

Thank you. Could you tell me where I missed in the N.E.C. 70?

You didn't miss anything. The NEC is not a school text book. You are expected to have a basic knowledge of electrical when you open the book.

 

[jumper]

Thank you. Could you tell me where I missed in the N.E.C. 70?

Second sentence.

300.3(C)

Conductors of Different Systems.
(1) 1000 Volts, Nominal, or Less. Conductors of ac and dc circuits, rated 1000 volts, nominal, or less, shall be permit- ted to occupy the same equipment wiring enclosure, cable, or raceway. All conductors shall have an insulation rating equal to at least the maximum circuit voltage applied to any conductor within the enclosure, cable, or raceway.

 

[Dennis Alwon]

Thank you. Could you tell me where I missed in the N.E.C. 70?

If the cord is rated 300 volts then it is not concerned with where the voltage comes from as long as it is not rated over 300 v.

If you have 240 volts phase to phase you still only have 240v on the cord. Same is true with 277 voltage to neutral. You still have under 300v on the cord

 

[broadgage]

BTW over here, most flexible cord and installation cable has two voltage markings, the lower one is the maximum voltage to ground and the higher one is the maximum between conductors.

300/500 volt is the most common for flexible cord. Installation cables may be either 300/500 volt or 600/1000 volt.

 

[jimmytee]

Thank you, almost all.