UL 60730-2-22
Standard for Automatic Electrical Controls - Part 2-22: Particular Requirements for Thermal Motor Protectors

Edition Number:1SCC Approved:--
Edition Date:2017-04-07DOD Approved: --
Price Code:FANSI Approved: 2017-04-07


    1 Scope and normative references

    This clause of Part 12 is applicable except as follows:

    2 References to "Part 1" in this document pertain to the fourth edition of IEC 60730-1 published in 2010.

    1.1 Replacement:

    This part of IEC 60730 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.

    NOTE 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;

    • 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 the contact material and eventually leading to failure of operation.

    Requirements concerning the testing of the combination of sealed (hermetic and semi-hermetic type) motor-compressors and THERMAL MOTOR PROTECTORS are given in IEC 60335-2-34.

    This standard applies to THERMAL MOTOR PROTECTORS using NTC or PTC thermistors, additional requirements for which are contained in Annex J.

    1.1DV Modification of 1.1 to by adding the following note after the third paragraph:

    NOTE Thermal motor protectors that are off-winding (not integrated with the motor winding) to the motor are covered under the scope of this part 2 and may be considered incorporated controls with respective to the requirements of this standard. Thermal protectors with integral heating elements (resistors, thermistors and the like) are considered voltage maintained thermal cutouts and are covered under UL 60730-2-9.

    1.1.1 This standard applies to the inherent safety, to the OPERATING VALUES, OPERATING TIMES, and OPERATING SEQUENCES, where such are associated with equipment safety, and to the testing of THERMAL MOTOR PROTECTORS used in or on household or similar equipment as well as sealed (hermetic and semi-hermetic type) motor-compressors.

    This standard applies to THERMAL MOTOR PROTECTORS for appliances within, but not limited to, the scope of IEC 60335-1 and its Part 2’s.

    NOTE Throughout this standard, the word “equipment” means “appliance and equipment”.

    THERMAL MOTOR PROTECTORS not intended for normal household use, but which nevertheless may be used by the public, such as equipment intended to be used by laymen in shops, in light industry and on farms, are within the scope of this standard.

    This standard does not apply to THERMAL MOTOR PROTECTORS designed exclusively for industrial applications.

    1.1.1DV Addition:

    1.1.1DV.1 This part 2 is to be used in conjunction with the latest edition of UL 60730-1 and its amendments.

    1.1.2 This standard does not apply to other means of motor protection.

    1.1.3 This standard does not apply to a manual device for opening the circuit.

    1.1.101DV Addition:

    1.1.101DV.1 This standard applies to thermal motor protectors designed for household, commercial, or industrial use.

    1.5 Normative references


    IEC 60269-3,  Low-voltage fuses – Part 3: Supplementary requirements for fuses for use by unskilled persons (fuses mainly for household and similar applications) – Examples of standardized systems of fuses A to F

    IEC 60335-2-34:2012,  Household and similar electrical appliances – Safety – Part 2-34: Particular requirements for motor-compressors

    Expand All

    • Cover
    • Transmittal
    • Table of Contents
    • UL Preface
    • Deviations
    • IEC Foreword
      • AUTOMATIC ELECTRICAL CONTROLS – Part 2-22: Particular requirements for thermal motor protectors
        • 1 Scope and normative references
          • 1.5 Normative references
        • 2 Definitions
          • 2.6 Definitions of type of automatic action of a control according to test procedure
          • 2.13 Miscellaneous definitions
        • 3 General requirements
        • 4 General notes on tests
        • 5 Rating
        • 6 Classification
          • 6.4 According to features of automatic action
          • 6.101 According to limited short-circuit capability
        • 7 Information
        • 8 Protection against electric shock
        • 9 Provision for protective earthing
        • 10 Terminals and terminations
          • 10.1 Not applicable.
          • 10.2 Terminals and terminations for internal conductors
        • 11 Constructional requirements
        • 12 Moisture and dust resistance
          • 12.2 Protection against humid conditions
        • 13 Electric strength and insulation resistance
        • 14 Heating
        • 15 Manufacturing deviation and drift
        • 16 Environmental stress
        • 17 Endurance
          • 17.1 General
          • 17.101 Limited short-circuit capability for thermal protectors classified under
        • 18 Mechanical strength
        • 19 Threaded parts and connections
        • 20 Creepage distances, clearances and distances through solid insulation
        • 21 Resistance to heat, fire and tracking
        • 22 Resistance to corrosion
        • 23 Electromagnetic compatibility (EMC) requirements – emission
        • 24 Components
        • 25 Normal operation
        • 26 Electromagnetic compatibility (EMC) requirements – immunity
        • 27 Abnormal operation
        • 28 Guidance on the use of electronic disconnection
    • Annexes
    • Annex E(normative)Circuit for measuring leakage current
    • Annex AA(informative)Endurance test for thermal motor protectors as components, i.e. not installed on a motor
    • Annex BB(informative)Testing of the combination of motor and thermal motor protectors (not applicable to sealed motor-compressors)
    • Annex CC(informative)Additional information on the application of motor protectors in pollution degree 1, 2 and 3
    • Bibliography