Single conductor on cable tray

[TMMB]

My Q is :Can i use single conductors for lighting circuits (2.5mm2), socket circuits (4mm2) and A/C split circuits (6mm2) on metal cable tray or not as per NEC??

 

[don_resqcapt19]

The smallest single conductor permitted in cable tray by the NEC is 1/0 and that is only in industrial occupancies.

 

[TMMB]

it is the same concept in office building?

 

[augie47]

it is the same concept in office building?

Yes. Look at Art 392.3 As Don stated, single conductors are only permitted in industrial establishments and then only for sizes 1/0 and larger and only then when they are listed and marked.