I wanted to inquire if it is possible to estimate available electrical capacity in an electrical distribution system based on only peak demand information available. For e.g. if an 800A, 347/600V, 3-phase electrical service has a peak demand of 175kW, would it be safe to assume the following calculation to estimate available electrical capacity at unity power factor:
800A x 0.8 = 640A (max. loading)
175kW = 600V x A x 1.732 i.e. A = 168A
Available capacity would be 640A - 168A = 472A.
Would the estimation of available capacity change if there are 600V - 208V step-down transformers downstream of the electrical distribution system?