UL Standard for Safety Automatic Electrical Controls – Part 2- 7: Particular Requirements for Timers and Time Switches
|Publication Date:||16 November 2020|
In general, this part of IEC 60730 applies to timers and time switches that may use electricity, gas, oil, solid fuel, solar thermal energy, etc. or a combination thereof, including heating, air conditioning and similar applications.
This standard is also applicable to individual timers utilized as part of a control system or timers which are mechanically integral with multifunctional controls having non-electrical outputs. This standard does not apply to time-delay switches (TDS) within the scope of IEC 60669-2-3.
NOTE 1 Throughout this standard, the word "timers" means timers and time switches, unless the type is specifically mentioned.
NOTE 2 Devices which only indicate time or passage of time are not included.
NOTE 3 This standard does not apply to multi-functional controls having an integrated timing function which is not capable of being tested as a separate timing device.
This standard applies to the inherent safety, to the operating characteristics where such are associated with equipment protection and to the testing of timers used in appliances and other apparatus, electrical and non-electrical, for household and similar purposes, but also extended to industrial purposes when no dedicated product standards exist, such as that for central heating, air conditioning, process heating, etc.
Timers for equipment 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 is also applicable to timers for appliances within the scope of IEC 60335-1.
This standard applies to manual controls when such are electrically and/or mechanically integral with timers.
This standard applies also to timers incorporating electronic devices, requirements for which are contained in Annex H.
This standard applies also to timers using NTC or PTC thermistors, requirements for which are contained in Part 1, Annex J.