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Use of NEC Tap Rule

Use of NEC Tap Rule

Use of NEC Tap Rule

(OP)
I have a situation where I have an existing 100 amp 3 phase service out of a panelboard. I would like to split the service in a junction box by terminating on a power distribution block and then feeding 3 individual 2 pole 30 amp receptacles mounted in the side of the jbox. There are #1AWG conductors coming in and I want to make the taps with #8AWG wire.

The receptacles are used to feed computer rack PDU's. The cord has no main breaker, but has 6 overload breakers(1 for 2 PDU receptacles) to protect the load side.

Is this a proper application of the NEC 240-21 10 foot tap rule?

RE: Use of NEC Tap Rule

The answer to your question is NO. Read 240.21(B)(3), which states the the tap conductors must be enclosed in a raceway. You need 3 each 2 pole overcurrent devices before your receptacles.
Without knowing the voltage and is it delta or wye system. I would use interlocking switch fuse receptacle so that the load is switched off before removing the plug cap. Also is this computer a critical operations data system? If it is, see Art. 708, 700, and 645.
BTW the term you FEEDER, not service. Please, next post include all pertinent info.
Good luck!

RE: Use of NEC Tap Rule

(OP)
After re-reading the code section several times, and finding some Mike Holt comments on the subject, it looks like you are correct. I do need that protective device before I go to any receptacle. Thanks for the input.

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