IEC 60947-8:2003+A1:2006+A2:2011 specifies rules for control units, which perform the switching functions in response to the thermal detectors incorporated in rotating electrical machines according to IEC 60034-11, and the industrial application. It specifies rules for that type of system comprising a positive temperature coefficient (PTC) thermistor detector having particular characteristics, and its associated control unit. The PT100 detectors are covered by IEC 60751, where the resistor values are given according to the temperatures of the detector. The present rules lay down the characteristics of association of this particular positive temperature coefficient thermistor detector and its associated control unit (designated "Mark A detector" and "Mark A control unit"), when they are used in thermal protection systems. The technical content is therefore identical to the base edition and its amendments and has been prepared for user convenience. It bears the edition number 1.2. A vertical line in the margin shows where the base publication has been modified by amendments 1 and 2.

This publication is to be read in conjunction with IEC 60947-1:2007

This consolidated version consists of the first edition (2003), its amendment 1 (2006) and its amendment 2 (2011). Therefore, no need to order amendments in addition to this publication.