UL 1973：2022 major modifications,
UL 1973,

▍BSMI Introduction Introduction of BSMI certification

BSMI is short for Bureau of Standards, Metrology and Inspection, established in 1930 and called National Metrology Bureau at that time. It is the supreme inspection organization in Republic of China in charge of the work on national standards, metrology and product inspection etc. The inspection standards of electrical appliances in Taiwan are enacted by BSMI. Products are authorized to use BSMI marking on the conditions that they are in compliance with safety requirements, EMC testing and other related tests.

Electrical appliances and electronic products are tested according to the following three schemes: type-approved (T), registration of product certification(R) and declaration of conformity (D).

▍What is the standard of BSMI?

On 20 November 2013, it is announced by BSMI that from 1^st, May 2014, 3C secondary lithium cell/battery, secondary lithium power bank and 3C battery charger are not permitted to access to Taiwan market until they are inspected and qualified according to the relevant standards (as shown in table below).

▍Why MCM?

● In 2014, rechargeable lithium battery became mandatory in Taiwan, and MCM began to provide the latest information about BSMI certification and the testing service for global clients, especially those from mainland China.

● High Rate of Pass: MCM has already help clients to obtained more than 1,000 BSMI certificates till now in one go.

● Bundled services: MCM helps clients successfully enter multiple markets in worldwide through one-stop bundled service of simple procedure.

UL 1973：2022 was published on 25th February. This version is based on two suggestion draft issued in May and October of 2021. The modified standard expands its range, including vehicle assistant energy system (e.g. illumination and communication).
Append 7.7 Transformer: transformer for battery system shall be certificated under UL 1562 and UL 1310 or relevant standards. Low voltage can be certificated under 26.6.
Update 7.9: Protective Circuits and Control: battery system shall provide switch or breaker, the minimum of which is required to be 60V instead of 50V. Extra requirement for instruction for overcurrent fuse Update 7.12 Cells (batteries and electrochemical capacitor): For rechargeable Li-ion cells, test under annex E is required, without considering UL 1642. Cells are required also to be analyzed if meet demand of safe design, like material and position of insulator, the coverage of anode and cathode, etc.
Append 16 High Rate Charge: Evaluate charging protection of battery system with over maximum charging current. Need to test in 120% of maximum charging rate.
Append 18 Overload Under Discharge: Evaluate battery system ability with overload under discharge. There are two conditions for the test: first is in overload under discharge in which current is higher than rated maximum discharging current but lower than current of BMS overcurrent protection; the second is higher than BMS over current protection but lower than level 1 protection current.