¹ Obtained from your utility bill as "Demand", "Peak Demand", "Billed Demand" or similar. If you don't have an electric bill enter the "amp" rating found on the main breaker for the facility.
² Lower loads means more likelihood of reverse current on one of the networks. Worst case is zero load. Select the lowest normal load you expect.
³ Starting at the main breaker or fusible switch, trace the circuit towards the utility until you reach the first transformer. If this transformer is owned by the utility, a call to the utility will usually result in your obtaining the information. If unsuccessful, select the "Not Sure" and the program will estimate the transformer rating as five times your incoming needs (assumes other customers are also using this transformer). Estimating that the upstream transformer is oversized is a conservative estimate since the likelihood of two mismatched sources successfully supplying a spot network decreases as the upstream transformer increases (actually as the upstream impedance decreases, but that is saying the same thing).
⁴ "%Z" is percent impedance. Provided on nameplate of transformer.
⁵ This is the rating of the proposed second source for your facility. As with question 4, you can obtain this information from your utility. If unsuccessful, select "Same as above" and the program will assume that the values for Source 2 are the same as for Source 1. For best operation, it is beneficial to have both source transformers having the same kVA and impedance ratings.