240volt hi-leg delta systems

[whe4]

does the NEC address allowing the reduction in size of the hi-leg.

 

[don_resqcapt19]

The conductor has to be sized per the load calculations and must be protected at or below its ampacity. This will permit the use of a reduced size high leg. I have seen 120/240 3 phase high leg systems with 3 different wire sizes. The smallest for the high leg, a bigger one for the grounded conductor and even larger ones for the other two phase conductors. About the only way to do this with the service condutors is to use fuses as the service overcurrent protective devices with a smaller fuse for the high leg.
Don

 

[LarryFine]

Another way, what we have in the restaurant we're doing, is a 200a, 1ph panel and a 100a, 3ph panel, from a common trough.