Instrumentation of 400-cycle aircraft electric systems

THE use of 400-cycle alternating current¹ as a power source on large aircraft originates the problem of adequate instrumentation at the distribution panel. Load conditions on a d-c system are determined by the simple parameters of voltage and current, whereas those of the a-c system include frequency and active and reactive power, in addition to voltage and current. Specifically, the flight engineer will require the following information for intelligent operation of the system: