What this document is
IS 16242 (Part 1):2014/IEC 62040-1:2008, the general and safety standard for uninterruptible power systems, has been revised and published as IS 16242 (Part 1):2025/IEC 62040-1:2017. On 21 August 2025 the BIS Registration Department issued this three-page guideline explaining how licensees and applicants make the change. It took effect immediately.
Two later circulars change it. On 10 October 2025 BIS corrected the standard number, which is to be read as IS 16242 (Part 1):2025/IEC 62040-1:2017 +AMD1:2021 +AMD2:2022 CSV. On 15 October 2025 BIS extended the deadline by a year. Both are listed above.
Key dates
- 21 August 2025: guideline issued, in force immediately.
- 19 November 2025: the original last date of concurrent running.
- 10 October 2025: standard number corrected to include IEC Amendments 1 and 2.
- 15 October 2025: BIS extended the last date of implementation.
- 19 November 2026: the last date now. After it, IS 16242 (Part 1):2014 stands withdrawn and no licence stays operative without compliance with the 2025 edition.
Existing licensees
- Move to IS 16242 (Part 1):2025 by 19 November 2026.
- Submit complete test reports from a BIS-recognised laboratory for every lead model in the licence that was tested to the 2014 edition.
- Give an undertaking that the other series models in the licence also meet the 2025 edition.
- If this is not done by the deadline, BIS is to start cancellation of the licence or removal of models from it.
New applicants and changes in scope
- Applications whose samples were already at the laboratory, or whose reports were already issued, can go ahead under the 2014 edition.
- New applications can be made under either edition until the last date. Under the 2014 edition, the applicant declares it will implement the 2025 edition by that date.
- No licence is granted under the 2014 edition after the last date.
- Changes in scope follow the applicant rules. Under the 2014 edition they are allowed only until the licensee switches over or until the last date, whichever is earlier.
What changed in the standard
The annexure lists the main changes, for general guidance:
- IEC 62477-1:2012 is used as a reference document.
- A definition of movable UPS has been added.
- The clause on flammability of enclosure materials has been modified.
- More working voltages in the creepage distance test, and extra requirements in the steady force, handle and control securement, touch current and temperature rise tests.
- The capacitor discharge test changes for pluggable type B UPS, with an added requirement for permanently connected UPS. The input current test is also modified.
- New tests for short-time withstand current, unsynchronised load transfer, loss of coolant, dry heat, damp heat and hydrostatic pressure.
Status
The guideline is current. The deadline of 19 November 2026 is close, so licensees who have not yet submitted 2025-edition reports should act now. The Phase II series guidelines still set the rules for grouping UPS models into a series.