SR EN 60947-8:2004

Low-voltage switchgear and controlgear -- Part 8: Control units for built-in thermal protection (PTC) for rotating electrical machines

Specifies rules for control units, which perform the switching functions in response to the thermal detectors incorporated in rotating electrical machines according to EN 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 EN 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. NOTE It is not possible to specify all the requirements for the operating characteristics of a control unit, as they are dependent on some aspects of the thermal detectors. Some aspects of the requirements of the thermal protector system can only be specified when account is taken of the characteri

Status : Valid
Approval date : 6/30/2004
Publish date : 7/1/2004
Withdrawal date : 1/11/2026
Number of pages : 34
ICS : 29.130.20 Low voltage switchgear and controgear
Technical Committee : 9 - Low-voltage switchgear and controlgear

Relations with other standards: