3 Phase Delta Feeders

[harley2g]

Can anyone please assist.

A colleague and i are discussing the requirements for a Delta Feeder.

The feeder originates from the service entrance equipment where there is a 3ph, 4w service, 2,000A.

There is a 400A Switchboard that is served from the 2,000A board.

All of the loads on the 400A switchboard are 3ph.

The feeder from the 2,000A Switchboard is 3-w+1GND.

Can any site the 2002 NEC that states a neutral is not required.

in anyones opinion is there a condition were pulling a neutral conductor would be of value to the 400A switchboard?

Thank you,
hg

 

[petersonra]

Re: 3 Phase Delta Feeders

If it is not needed, you are not required to run it. However, if you have a neutral, it might make sense to run it with the feeder if there is a chance it will be needed down the road.

The code does not require you to run a wire that is not used.

Since you indicated this is a delta feed, and used the word neutral with it, and indicated you would need an extra wire to run the neutral, I can only guess this is a delta with a midpoint ground.

 

[steve66]

Re: 3 Phase Delta Feeders

For a code reference, how about 215.7 of teh 2002 NEC:

Two wire DC circuits and ac circuits of two or more ungrounded conductors shall be permitted to be tapped from the ungrounded conductors of circuits having a grounded neutral conductor. Switching devices in each tapped circuit shall have a pole in each ungrounded conductor.

Steve

 

[jim dungar]

Re: 3 Phase Delta Feeders

It sounds like you have a 4 wire + gnd service and only want to bring 3W + gnd to a distribution panel.

You will not find any NEC prohibition to doing this.

Like petersonra said, the NEC does not require you to run unused conductors. If it did, then you should be running neutrals all the way down to all of your motors.