BS EN 61558-2-16:2009+A1:2013

Safety of transformers, reactors, power supply units and similar products for supply voltages up to 1 100 V. Particular requirements and tests for switch mode power supply units and transformers for switch mode power supply units | Status: Current, Superseded

1 Scope Replacement: This part of IEC 61558 deals with the safety of switch mode power supply units and transformers for switch mode power supply units. Transformers incorporating electronic circuits are also covered by this standard.

NOTE 1 Safety includes electrical, thermal and mechanical aspects.

This part applies to:

1. a) switch mode power supply units incorporating safety isolating transformers providing SELV, PELV or FELV a.c. or d.c. output voltage(s), or a combination thereof according to IEC 61140 and IEC 60364‑4‑41 for use with household and other consumer products, except for products covered by IEC 60065, IEC 61347 series, IEC 61204‑7 and IEC 60950‑ 1;
2. b) switch mode power supply units with a maximum output voltage not exceeding 1 000 V a.c. or 1 414 V ripple-free d.c. for use with household and other consumer products, except for products covered in a) and products covered by IEC 60065, IEC 61347 series, IEC 61204‑7 and IEC 60950‑1;
3. c) this standard may be used for transformers for use in switch mode power supply units (see Annex BB).

This part covers the safety requirements for:

• • separating SMPS for general use corresponding to Part 2-1;
• • isolating SMPS for general use corresponding to Part 2-4;
• • safety isolating SMPS for general use corresponding to Part 2-6;
• • auto-SMPS for general use corresponding to Part 2-13.

For SMPS for specific application corresponding to the other Parts 2 of 61558 series, the necessary requirements of the relevant Parts 2 are applicable. In addition, the requirements listed in this part apply. Where the two requirements are in conflict, the most severe take precedence.

NOTE 2 As the maximum rated supply voltage of the internal transformer is 1 000 V, the maximum rated supply voltage of the switch mode power supply may be lower due to type of rectification.

Switch mode power supply units covered by this standard are air cooled (natural or forced) independent, associated, stationary, portable, single-phase, or polyphase, with the rated supply voltage not exceeding 1 100 V a.c., the rated supply frequency not exceeding 500 Hz, the rated internal operating frequency exceeding 500 Hz, but not exceeding 100 MHz, and the rated output not exceeding 1 kVA or 1 kW, incorporating dry-type transformers with encapsulated or non-encapsulated windings. Associated transformers for switch mode power supply units covered by Annex BB of this standard shall have a rated output not exceeding:

• – 25 kVA for single-phase transformers;
• – 40 kVA for polyphase transformers.

NOTE 3 For higher frequencies, additional requirements may be necessary. However, this standard may be used as a guide.

The no-load output voltage or the rated output voltage of switch mode power supply units shall not exceed:

• – 1 000 V a.c. or 1 415 V ripple-free d.c. when separating transformers or auto-transformers are used;
• – 500 V a.c. or 708 V ripple-free d.c. when isolating transformers are used;
• – 50 V a.c. or 120 V ripple-free d.c. when safety isolating transformers are used.

The no-load output voltage or the rated output voltage of independent switch mode power supply units shall not be less than:

• – 50 V a.c. or 120 V ripple-free d.c. when separating transformers or autotransformers are used.

This standard is also applicable to switch mode power supply units, converters and inverters without limitation of the rated output. However, such switch mode power supply units are for special applications and are subject to an agreement between the purchaser and the manufacturer.

NOTE 4 In the context of this standard, converters and invertors are considered to be switch mode power supply units.

This standard may also be used as a guide for products not covered by the scope of this standard, the scope of IEC 61204‑7, or the scope of IEC 61347 series. This standard does not apply to:

• – motor-generator sets;
• – uninterruptible power supplies (UPS) according to IEC 62040;
• – switch mode power supply units covered by IEC 61204‑7 (i.e., low-voltage power supply devices, d.c. output, performance characteristics) and d.c. power and distribution equipment and switch mode power supply units for use in applications covered by IEC 60950‑1, IEC 61010‑1, IEC 60601‑1, and IEC 60065;
• – lamp control gear covered by IEC 61347‑1;
• – external circuits and their components intended to be connected to the input terminals and output terminals of the transformers.

NOTE 5 IEC 61204‑7 will be updated by SC 22E.

NOTE 6 Attention is drawn to the following:

• – for transformers intended to be used in vehicles, on board ships and aircraft, additional requirements (from other applicable standards, national rules, etc.) may be necessary;
• – measures to protect the enclosure and the components inside the enclosure against external influences such as fungus, vermin, termites, solar-radiation, and icing should also be considered;
• – the different conditions for transportation, storage, and operation of the transformers should also be considered;
• – additional requirements in accordance with other appropriate standards and national rules may be applicable to transformers intended for use in special environments, such as tropical environment.

NOTE 7 Future technological development of transformers may necessitate a need to increase the upper limit of the frequencies; until then, this part may be used as a guidance document.

Unless otherwise specified, from here onward, the term SMPS covers switch mode power supply units.