§ 111.51-4 - Short-circuit calculations for systems 1500 kilowatts or above.

§ 111.51-4 Short-circuit calculations for systems 1500 kilowatts or above.

Short-circuit calculations must be submitted for systems with an aggregate generating capacity of 1500 kilowatts or more by utilizing one of the following methods:

(a) Exact calculations using actual impedance and reactance values of system components.

(b) Estimated calculations using IEC 61363–1:1998 for AC systems and IEC 61660–1:1997 for DC systems (both incorporated by reference; see § 110.10–1 of this subchapter).

(c) The estimated calculations using a commercially established analysis procedure for utility or industrial applications.