BS 4999-111:1987
Superseded
A superseded Standard is one, which is fully replaced by another Standard, which is a new edition of the same Standard.
A superseded Standard is one, which is fully replaced by another Standard, which is a new edition of the same Standard.
General requirements for rotating electrical machines Specification for built-in thermal protection for electric motors rated at 660 volts a.c. and below
Hardcopy , PDF
09-02-2005
English
27-02-1987
Foreword
Committees responsible
Introduction
Specification
1 General
1.1 Scope
1.2 Definitions
2 Requirements for devices fitted into motor windings
2.1 General
2.2 Classification
2.3 Motors fitted with thermistors
2.4 Motors fitted with thermostats
3 Temperature sensitive resistors (thermistors)
3.1 General
3.2 Characteristics
3.3 Ability to withstand motor manufacturing processes
3.4 Dimensions
3.5 Leads
3.6 Marking
3.7 Type tests
3.8 Routine tests
4 Thermistor control unit
4.1 Terminals
4.2 Standard operating conditions
4.3 Drop-off (trip) and pick-up (re-set) resistance
4.4 Thermistor applied voltage
4.5 Abnormal conditions
4.6 Minimum voltage hold-in
4.7 Switching rating
4.8 Type tests
4.9 Routine tests
5 Thermostats
5.1 General
5.2 Characteristics
5.3 Ability to withstand motor manufacturing processes
5.4 Leads
5.5 Marking
5.6 Switching rating
5.7 Overload switching performance
5.8 Type tests on thermostats
Appendix
A Typical characteristic of PTC type thermistor
Tables
1 Winding temperature
2 Recommended reference temperatures for thermistors
Access your standards online with a subscription
Features
-
Simple online access to standards, technical information and regulations.
-
Critical updates of standards and customisable alerts and notifications.
-
Multi-user online standards collection: secure, flexible and cost effective.