IEC 60947-4-2:2020 applies to semiconductor motor controllers, starters and soft-starters which can include a series mechanical switching device, intended to be connected to circuits the rated voltage of which does not exceed 1 000 V AC. This fourth edition cancels and replaces the third edition published in 2011.Jun 26, 2020
Is IEC 60947-4-1 standard?
IEC 60947-4-1:2018 is available as IEC 60947-4-1:2018 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.
What IEC 947?
Today, conformity with standard IEC 947-2, published in 1989 and reviewed and completed in 1995, can be considered as an « all-risks insurance » guaranteeing a circuit breaker's fitness for use. Quite remarkably all countries, except Japan, have approved this standard.
What is IEC 947 2?
IEC 947-2 defines two categories of circuit breakers: c those of category A for which no short-circuit trip delay is provided. These are generally moulded case circuit breakers such as Compact NS. This requirement is not synonymous with non-discrimination on tripping (see « Cahier Technique » n° 167).