This standard is applicable to portable phase comparators with or without a built-in power source to be used on electrical systems for voltages of 1 to 36 kV a.c. and frequencies from 50 Hz to 60 Hz. This standard is applicable to two-pole phase comparators having a connection lead between them, two-pole phase comparators operating with a wireless connection and single-pole phase comparators operating with a memory system. This standard is applicable to phase comparators used in contact with the part to be tested, as a single unit or as a separate device completed by an adaptable insulating pole covered in IEC 60855 or IEC 61235. Some restrictions on their use are applicable in the case of factor-assembled switchgear and on overhead systems of electrified railways (see annex B). Devices which can be used as voltage detector and phase comparator are not covered by this standard.