IEC 62040-1:2021 pdf download – Uninterruptible power systems (UPS) – Part 1: Safety requirements.
3.101 uninterruptible power system UPS combination of convertors, switches and energy storage devices (such as batteries), constituting a power system for maintaining continuity of load power in case of input power failure Note 1 to entry: Continuity of load power occurs when voltage and frequency are within rated steady-state and transient tolerance bands, and with distortion and interruptions within the limits specified for the output port. Input power failure occurs when voltage and frequency are outside rated steady-state and transient tolerance bands, or with distortion or interruptions outside the limits specified for the UPS. 3.102 skilled person person with relevant education and experience to enable him or her to perceive risks and to avoid hazards which the equipment can create Note 1 to entry: Such person has access to restricted access areas. [SOURCE: IEC 60050-195:1998, 195-04-01, modified – The word “(electrically)” has been deleted from the term, and “electricity” has been replaced by “the equipment” in the definition. The note has been added.] 3.103 instructed person person adequately advised or supervised by skilled persons to enable him or her to perceive risks and to avoid hazards which the equipment can create Note 1 to entry: Such person has access to restricted access areas. Note 2 to entry: Examples of activities performed by an instructed person can be found in IEC 61140:2001, Clause 8. [SOURCE: IEC 60050-195:1998, 195-04-02, modified – The word “(electrically)” has been deleted from the term, and the notes have been added.]
3.120 rated conditional short-circuit current I cc RMS value of prospective short-circuit current , declared by the UPS manufacturer, that can be withstood for the total operating time (clearing time) of the short-circuit protective device (SCPD) under specified conditions Note 1 to entry: The short-circuit protective device does not necessarily form an integral part of the UPS. [SOURCE: IEC 61439-1:2011, 3.8.10.4, modified – The word “RMS” has been added to “value”, the word “assembly” has been replaced by ” UPS”, and the note has been rephrased.] 3.121 low impedance path path containing devices that for UPS load purposes present negligible impedance, such as cabling, switching devices, protecting devices and filtering devices Note 1 to entry: The devices in a low impedance path generally present current limiting characteristics under short-circuit conditions. Note 2 to entry: Examples include current limiting fuses, current limiting circuit-breakers, transformers and inductors. 3.122 prospective short-circuit current I cp RMS value of the current which would flow if the supply conductors to the circuit are short- circuited by a conductor of negligible impedance located as near as practicable to the supply terminals of the UPS [SOURCE: IEC 61439-1:2011, 3.8.7, modified – The word “assembly” has been replaced by “UPS”.]
3.125 reference test load load or condition in which the output of the UPS delivers the active power (W) for which the UPS is rated Note 1 to entry: This definition permits, when in test mode and subject to local regulations, the UPS output to be injected into the input AC supply. [SOURCE: IEC 62040-3:2011, 3.3.5] 3.126 reference non-linear load non-linear load that when connected to a UPS, consumes the apparent power at which the UPS shall be tested Note 1 to entry: Refer to Clause BB.5 for test details. [SOURCE: IEC 62040-3:2011, 3.3.6, modified – The expression “the apparent and active power for which the UPS is rated in accordance with Annex E” has been replaced by “the apparent power at which the UPS shall be tested”, and the note has been added.] 3.127 backfeed condition in which a voltage or energy available within the UPS is fed back to any of the input terminals, either directly or by a leakage path while operating in the stored energy mode and with primary power not available [SOURCE: IEC 62040-3:2011, 3.2.3, modified – The words “while AC input power is” have been replaced by “with primary power “.] 3.128 backfeed protection control scheme that reduces the risk of electric shock due to backfeed