How do I calculate what load I need to add to an electrical service for an x-ray machine. I see the code says 50% of maximum momentary current draw(would be 75 amps in this case) for the the branch circuit conductors and disconnect. Does this apply to the service as well, this suite only has 200 amp service and it has everything else electric so it I have to use the 75 amps as the demand on the service I will need to upgrade the service.