Uninterruptible power systems (UPS) - Part 3: Method of specifying the performance and test requirements

Overview

IEC 62040-3:2021 is the performance and test standard for static UPS, prepared by IEC TC 22. It applies to systems supplied from AC up to 1 000 V, with AC output up to 1 000 V and energy storage up to 1 500 V DC, whose primary function is continuity of load power. Edition 3 was published on 21 April 2021, runs to 94 pages and is a paid standard; this record rests only on the publisher's public abstract.

The products outside its scope are named explicitly: distribution boards, stand-alone static transfer switches (IEC 62310-3), rotary UPS (IEC 88528-11) and DC UPS (IEC 62040-5-3). This boundary clarifies which equipment the document is a reference for. A rotary UPS or stand-alone transfer switch in a facility therefore needs other standards; this document governs only the performance definition and tests of static UPS.

The main changes in the 2021 edition are these. The performance classification coding was shortened from 8 to 7 characters (5.3.4). The minimum UPS efficiency values in Annex I became normative, based on the active output power rating and weighting factors. The non-linear step load is no longer a type test, and multiple normal-mode test requirements were introduced. These changes aim to make product comparison and efficiency claims more consistent.

Because the record is not based on the full text, the meaning of each classification character, the efficiency thresholds and the details of the test procedures are not given here; the standard itself must be consulted. IEC 62040-1, IEC 62040-5-3, the EU Code of Conduct for AC UPS and TS EN IEC 62040-3 are named as related documents. The most practical consequence for a designer is to base UPS selection on efficiency at standard-defined load points rather than on a single nameplate figure.

Key points

1. The standard applies to static UPS supplied from AC <= 1 000 V, with AC output <= 1 000 V and energy storage <= 1 500 V DC.
2. Distribution boards, stand-alone STS (IEC 62310-3), rotary UPS (IEC 88528-11) and DC UPS (IEC 62040-5-3) are excluded.
3. The performance classification coding was shortened from 8 to 7 characters (5.3.4).
4. Minimum UPS efficiency values in Annex I became normative, based on active output power rating and weighting factors.
5. The non-linear step load is no longer a type test; multiple normal-mode test requirements were introduced.
6. Edition 3 was published on 21 April 2021 and has 94 pages.
7. Related documents: IEC 62040-1, IEC 62040-5-3, EU Code of Conduct for AC UPS and TS EN IEC 62040-3.
8. The standard is paid; this record rests on the public catalogue abstract.

Using it in design

• In the UPS catalogue, store the IEC 62040-3 classification (for example VFI-SS-111).
• Store efficiency at 25/50/75/100 % load and apply the Annex I minimum check.
• In the energy model, interpolate this curve at actual load rather than using a single nameplate efficiency.
• For designs including rotary UPS, DC UPS or stand-alone STS, refer to the separate relevant standards.

Who should read it

Electrical engineers selecting and specifying UPS, designers building energy models and procurement teams.

Related standards

• IEC 62040-1
• IEC 62040-5-3
• EU Code of Conduct for AC UPS
• TS EN IEC 62040-3

Publication details

Authors

IEC TC 22

Publisher

IEC

Year

2021

Document number

IEC 62040-3:2021

Document language

English

Source type

Standard

Access

Citation only

Licence

Copyright retained; citation only — the publisher’s terms apply to the original document

Citation