Electrical safety in low voltage distribution systems up to 1 000 V a.c. and 1 500 V d.c. - Equipment for testing, measuring or monitoring of protective measures - Part 7: Phase sequence (IEC 61557-7:2019)
This part of IEC 61557 specifies the requirements applicable to measuring equipment for
testing the phase sequence in three-phase distribution systems. Indication of the phase
sequence can be mechanical, visual and/or audible.
This document does not apply to additional measurements for other quantities. It does not
apply to monitoring relays.
NOTE Common worldwide three-phase distribution systems are depicted in IEC 610101
ΚΩΔΙΚΟΣ ΠΡΟΪΟΝΤΟΣ:
CYS EN IEC 61557-7:2022
This part of IEC 61557 specifies the requirements applicable to measuring equipment for
testing the phase sequence in three-phase distribution systems. Indication of the phase
sequence can be mechanical, visual and/or audible.
This document does not apply to additional measurements for other quantities. It does not
apply to monitoring relays.
NOTE Common worldwide three-phase distribution systems are depicted in IEC 610101