Automatic electrical controls - Part 2-22: Particular requirements for thermal motor protectors

IEC 60730-2-22:2014 applies to the partial evaluation of thermal motor protectors as defined in IEC 60730-1 for household and similar use, including heating, air conditioning and similar applications as well as for sealed (hermetic and semi-hermetic type) motor-compressors. A thermal motor protector is considered an integrated control since its protective functionality is dependent on the correct mounting and fixing in or on a motor and which can only be fully tested in combination with the relevant motor. This dependency is illustrated by:

- the ability of the thermal motor protector to accurately and reliably sense the heat of the motor windings;

- thus, addressing the over-temperature protection due to motor overload conditions;

- the ability of the thermal motor protector to accurately and reliably sense the current due to motor locked-rotor conditions;

- thus, reducing the response time and not being adversely affected by heat-sink at the assembly spot in the application and the influence of the motor's electromagnetic field on the switch behaviour of the thermal motor protector;

- particularly, affecting the arc direction between the contacts resulting in uneven wear of