1910.304(f)(2)(iv) The Following Additional Requirements Apply to Feeders Only:

The continuous ampere rating of a fuse may not exceed three times the ampacity of the conductors. The long-time trip element setting of a breaker or the minimum trip setting of an electronically actuated fuse may not exceed six times the ampacity of the conductor. for fire pumps, conductors may be protected for short circuit only; and

Conductors tapped to a feeder may be protected by the feeder overcurrent device where that overcurrent device also protects the tap conductor.