DIN EN 60947-4-1:2011-01

This part of IEC 60947 applies to the types of equipment given below the main circuits of which are intended to be connected to circuits, the rated voltage of which does not exceed 1 000 V a.c. or 1 500 V d.c. Starters and/or contactors which comply with this standard are not normally designed to interrupt short-circuit currents. Therefore, suitable short-circuit protection forms part of the installation, but not necessarily a part of the contactor or starter. In this context, this standard contains requirements for - contactors associated with overload and/or short-circuit protective devices; - starters associated with separate short-circuit protective devices and/or separate short-circuit and integrated overload protective devices; - contactors or starters which are combined under specified conditions with their short-circuit protective devices. Such combinations, for example, combined starters or starters protected against short circuits, are rated as a unit. For circuit-breakers and fuse combination units as short-circuit protection devices in combined starters and starters protected against short-circuits, the requirements in accordance with IEC 60947-2 or IEC 60947-3 apply. This standard applies to the following equipment: - a.c. and d.c. contactors, - d.c. motor-starters, - direct-on-line starters (at full voltage) for a.c., - reduced voltage starters for a.c., - star-delta starters, - two-step auto-transformer starters, - rotor resistance starters. With regard to the previous edition, the following changes have been made: - the test at -5 °C and at +20 °C has been deleted for thermal overload relays which are not compensated for ambient air temperature has been deleted, - conditions for the tests according to Annex Q of IEC 60947-1 have been incorporated, - EMC tests: the acceptance criteria have been improved and adapted to IEC 60947-1 for fast transients, - the duration of the insulation test voltage has been changed from 5 s to 60 s for the I_CD test in Annex B, - the statistical considerations of the electrical endurance have been improved, - in Annex H, new expanded functions in electronic overload relays have been explained more clearly and supplemented, - Annex K "Method for determining data for electromechanical contactors in applications with functional safety" has been newly added. The responsible Committee is K 431 "Niederspannungsschaltgeräte und -kombinationen" ("Low-voltage switchgear and controlgear assemblies") of the DKE (German Commission for Electrical, Electronic and Information Technologies) at DIN and VDE.