Parallel Conductors with All Phases in Same Raceways

[Jsim4109]

I know installing all the A phases in the same raceways, All the B Phases and all the C Phases in metal raceways leads to issues like EMF and heating, but is there a code article discussing this? I have a client insisting it is acceptable and Im looking for backup tp support we should not do this. See attached picture. He wants to install all the A phases in one set, B in another and C in the third. The wiring method is single conductor tray cable from cable tray entering those holes with CGB fittings.

Thank you.

 

[infinity]

Look at 300.3(B)(1)Exception

 

[xptpcrewx]

I know installing all the A phases in the same raceways, All the B Phases and all the C Phases in metal raceways leads to issues like EMF and heating, but is there a code article discussing this? I have a client insisting it is acceptable and Im looking for backup tp support we should not do this. See attached picture. He wants to install all the A phases in one set, B in another and C in the third. The wiring method is single conductor tray cable from cable tray entering those holes with CGB fittings.

Thank you.

Look at 300.3(B)(1)Exception

Section 300.20 (A) and (B) cover this.

If the phase conductors are ran in this manner over a considerable distance, the inductive reactance might be considerably higher. This could have a negative effects on voltage regulation/imbalance as well as the short-circuit current seen by upstream protective devices... not advised.

 

[wwhitney]

So if the plate with the six holes are the only holes used, and the plate is aluminum, then what the client proposes is acceptable, right? Within the cable tray, would it make sense to regroup the conductors into identical groups which have all phases, by passing conductors over each other to reorder them?

Cheers, Wayne

 

[Jsim4109]

These are all awesome. thank you so much.

 

[infinity]

So if the plate with the six holes are the only holes used, and the plate is aluminum, then what the client proposes is acceptable, right? Within the cable tray, would it make sense to regroup the conductors into identical groups which have all phases, by passing conductors over each other to reorder them?

Cheers, Wayne

The raceway has to be non-metallic and run underground to utilize iso-phase.

 

[wwhitney]

The raceway has to be non-metallic and run underground to utilize iso-phase.

The OP speaks of raceways but then says "The wiring method is single conductor tray cable from cable tray entering those holes with CGB fittings." So 300.3(B) isn't an issue, as far as I can see.

[Edit: although I just saw the reference to 392.20(C), which requires that the parallel sets be grouped consisting of all phases. So the reordering I suggested earlier would be mandatory, and then the question is whether it is allowed to switch to single phase groups as the conductors go through the aluminum plate.]

Cheers, Wayne