3 phase

You cannot put each individual phase though a separate hole in a metal box, you must put all 3 phases through one hole. If you have parallel conductors that require multiple conduits, each conduit must contain conductors from all 3 phases, especially if they pass through a metal box. If you separate the phase conductors and pass them through a metal wall separately, there will be severe inductive heating of the metal that will likely start a fire.

Dear all,

If you need to pull three phase conductors into separate holes in a metal plate, use aluminum plate.

Regards

A qualified and experienced electrical installer can advise on best local practices.