SC 121A

IEC 60947-6-2:2020 This document applies to control and protective switching devices (or equipment) (CPS), the main contacts of which are intended to be connected to circuits of rated voltage not exceeding 1 000 V AC or 1 500 V DC.
It covers control and protective switching device (CPS):

• which provides protective and control functions for circuits and motors;
• where its control function is operated exclusively otherwise than by hand;
• which provides continuity of service after over-current conditions; and
• which can have additional functions, such as isolation or communication.

This third edition cancels and replaces the second edition published in 2002 and its Amendment 1:2007. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:

• editorial changes according to ISO/IEC directives Part 2,
• alignments with IEC 60947-1:2020:
  • markings ("s", "sol", "r" or "f");
  • constructional requirements including material requirements;
  • requirements for screwless terminals;
  • measurement method of the pole impedance;
  • EMC requirement and testing;
  • procedure to determine data for electromechanical CPS’s used in functional safety applications;
• harmonisation with IEC 60947-2:2016:
  • operation tests of under-voltage relays and shunt releases;
  • CPS for IT systems (Annex G);
  • coordination with other short-circuit protective devices;

• alignments with IEC 60947-4-1:2018:
  • test at the rated conditional short-circuit current Iq of protected switching devices;
  • short-circuit tests harmonisation with North America;
  • reliability data for functional safety applications (new Annex K);
  • safety aspects related to electronic circuits and protective impedance (new Annex N);
  • introduction of provisions covering the impact of higher locked rotor current to achieve high efficiency class;
  • mention of dedicated wiring accessories;
  • definitions and measurement method of the power consumption of the control circuit during holding and pick-up operations;
  • load monitoring indicators (new Annex M).