BS 7767:1994

This standard BS 7767:1994 Method for assessing the short-circuit withstand strength of partially type-tested assemblies (PTTA) is classified in these ICS categories:

• 29.130.20 Low voltage switchgear and controlgear

This Technical Report describes an extrapolation method for assessing the short-circuit withstand strength of partially type-tested assemblies (PTTA).

Method of extrapolation which may be used for partially type-tested assemblies to prove compliance with the requirements of 7.5.1 of IEC 60439-1.