Re: X-Ray & Service Calculation
I would think the calculated load that you would apply to your service calculations for X-ray equipment would be based on the feeder load to this equipment.
660.6 Rating of Supply Conductors and Overcurrent Protection.
(B) Feeder Conductors. The rated ampacity of conductors and overcurrent devices of a feeder for two or more branch circuits supplying X-ray units shall not be less than 100 percent of the momentary demand rating [as determined by 660.6(A)] of the two largest X-ray apparatus plus 20 percent of the momentary ratings of other X-ray apparatus.
FPN:The minimum conductor size for branch and feeder circuits is also governed by voltage regulation requirements. For a specific installation, the manufacturer usually specifies minimum distribution transformer and conductor sizes, rating of disconnect means, and overcurrent protection.
If this is only one x-ray equipment then I would say look at.
660.6 Rating of Supply Conductors and Overcurrent Protection.
(A) Branch-Circuit Conductors. The ampacity of supply branch-circuit conductors and the overcurrent protective devices shall not be less than 50 percent of the momentary rating or 100 percent of the long-time rating, whichever is greater.
