taps

[lmchenry]

Here is the situation. 400 amp disconnect, 3 phase, 4 subpanels (MLO) fed off of taps from each lug of the phase. All 4 conductors under one lug. Aluminum and copper conductors. (4/0 al, 2cu, 1cu, 6cu) Subpanels within 10 ft. Questions: Can you put different and multiple conductors under one lug? Don't the subpanels need ocpd?

 

[M. D.]

In my opinion, the trmination is in all likelyhood a violation and the taps would require OCP at the termination point.

 

[raider1]

Here is the situation. 400 amp disconnect, 3 phase, 4 subpanels (MLO) fed off of taps from each lug of the phase. All 4 conductors under one lug. Aluminum and copper conductors. (4/0 al, 2cu, 1cu, 6cu) Subpanels within 10 ft. Questions: Can you put different and multiple conductors under one lug? Don't the subpanels need ocpd?

The lugs would have to be listed for multiple wires and also listed for both copper and aluminum. See 110.14(A)

As for the overcurrent protection of the tap conductors take a look at 240.21(B).

Chris