1.1   This part of IEC 61534 specifies general requirements and tests for powertrack (PT) systems with a rated voltage not exceeding 277 V a.c. single phase, or 480 V a.c. two or three phase [A1_start]50 Hz or 60 Hz[A1_end] with a rated current not exceeding 63 A. These systems are used for distributing electricity in household, commercial and industrial premises.