Class 2 and 480v enclosures

[MH61]

I am installing Automatic Temperature Controls in a commercial building. I have to control 480v 3 phase exhaust fans from the customers class 2 Digital Control system. The class 2 wiring is only rated for 300v. There is a low voltage control relay in the fan starter for stop start control and a current switch around one motor lead, which is a status to the digital controller. which code applies to my situation, Article 300.4(C)(1) which would not permit the class 2 wiring or is Note 1 under this article which refers to 724.136 (D) which would allow class 2 as long as there is a 0.25 in. separation from conductors

 

[tom baker]

Yes 725.136 (D) would allow the Class 2 circuit as long as the separation is maintained. The general rule is no class 2 with light, power in enclosures, raceways or boxes, but often the class 2 has to be in the enclosure for termination. Often mfgs have barriers or similar.