Low - Voltage switchgear and controlgear: a.c semiconductor motor controllers and starters-IS/IEC 60947-4-2 : 2011

Semiconductor Motor Controllers

IEC 60947-4-2:2011 applies to a.c. semiconductor motor controllers and starters, which may include a series mechanical switching device, intended to be connected to circuits, the rated voltage of which does not exceed 1 000 V a.c. This standard characterizes a.c. semiconductor motor controllers and starters with and without bypass means

This third edition replaces the second edition published in 1999 and its Amendments 1 (2001) and 2 (2006). It is a technical revision.

This standard characterizes a.c. semiconductor motor controllers and starters with and without bypass means. This third edition replaces the second edition published in 1999 and its Amendments 1 (2001) and 2 (2006). It is a technical revision.

This edition includes the following significant technical changes with respect to the previous edition and its amendments:

updated EMC normative references and associated requirements,
new references to IEC 60947-1,
marking of electronic relays without thermal memory,
marking of tripping time at 0 °C ambient or below,
new test requirements for limits of operation of time-delay overload relays,
new classes of overload current withstand time,
damp heat, salt mist, vibration and shock tests,
short-circuit test in the smallest enclosure,
update of the routine and sampling tests.