Skip navigation

New External Power Supply Standards: 62368 to Replace 60950 and 60065 UPDATE

If you design or use external power supplies, you should mark December 2020 on your calendar.

December 2020 is the Date of Withdrawal (DoW) of the standards to supersede IEC 60065 and IEC 60950-1. The new standard is IEC 62368, which will replace 60065 (Audio/Video) and 60950 (IT) for external power supplies. IEC 62368-1 was published in Europe during the second half of 2014. Originally the DoW was June 2019, but was changed to December 2020.

The existing 60950 standard is applicable to mains-powered or battery-powered information technology equipment—including electrical business equipment and associated equipment—with a rated voltage not exceeding 600 V and designed to be installed in accordance with the Canadian Electrical Code, Part I, CSA C22.1-12; General Requirements – Canadian Electrical Code, Part II, CSA C22.2 No. 0-10; the National Electrical Code, NFPA 70-2014; and the National Electrical Safety Code, IEEE C2-2012.

The 60950 standard is also applicable to equipment, unless otherwise identified by a marking or instructions, designed to be installed in accordance with Article 645 of the National Electrical Code, ANSI/NFPA 70, and the Standard for the Protection of Information Technology Equipment, NFPA 75-2013.

In addition, this standard is also applicable to information technology equipment:

  • Designed for use as telecommunication terminal equipment and telecommunication network infrastructure equipment, regardless of the source of power;
  • Designed and intended to be connected directly to, or used as infrastructure equipment in, a cable distribution system, regardless of the source of power;
  • Designed to use the AC mains supply as a communication transmission medium (see Clause 6, Note 4 and 7.1, Note 4).

IEC 60950 is also applicable to:

  • Components and subassemblies intended for incorporation in this equipment. Such components and subassemblies need not comply with every requirement of the standard, provided that the complete equipment, incorporating such components and subassemblies, does comply;
  • External power supply units intended to supply other equipment within the scope of this part of IEC 60950;
  • Accessories intended to be used with equipment within the scope of this part of IEC 60950.

Replacing IEC 60950 is the new safety standard for Information Technology Equipment and Audio/Video Equipment, IEC 62368-1. It is a hazard-based, performance-oriented standard. Technology is changing, and IEC 62368-1 is technology independent. It also minimizes the need for national/regional differences.

The United States (ANSI-UL 62368-1), Canada (CSA C22.2 No 62368-1), Denmark, Netherlands, and South Africa adopted national versions. Edition No. 1 was not supported by Europe (CENELEC), which wanted further refinement of requirements before adoption. In Asia, multiple countries are doing a close study of it. For the IECEE CB Scheme, IEC 62368-1 has been activated under OFF/TRON that accounts for more than half of CB Scheme certifications. The IECEE CB Scheme is an international system for mutual acceptance of test reports and certificates dealing with the safety of electrical and electronic components, equipment, and products.

Edition No. 2 of IEC 62368-1 (108/495A/CDV) had a closing date for voting of March 1, 2013. The IEC target publication date was the second half of 2013. It is expected that Europe will adopt EN 62368-1, 2nd edition, with a likely five-year effective date. The target publication date of Edition No. 2 of CSA/UL 62368-1 was 2014, with a likely five-year effective date.

UL has now also assigned a December 20, 2020 effective date for new equipment/certifications of A/V, IT, or ICT equipment, or significant modification of existing equipment/certifications. Continuing certification will be allowed for existing certifications that are not significantly modified after the date. Like in the EU, this date is aligned with the adoption period recommended by IEC TC108 and it will allow AV and ICT equipment manufacturers to both adequately prepare for the transition to the new standard and align their certification strategies to cover two main regions of the world. More information on the associated UL Effective Dates for all the primary UL A/V and ICT standards is outlined in this blog post.

Click here for the UL website and additional UL standards information:

IEC 62368-1 Test Report Form (TRF) and Test Equipment List. For manufacturers and stakeholders interested in the TRF for IEC 62368-1 Ed. 2, it is available from the IEC Webstore. Similarly, the provisional 62368-1 Test Equipment List for Ed. 2 is available from IECEE.

No-Load Power and Efficiency

The international efficiency marking protocol defines two performance criteria; no-load power consumption (Low Voltage Directive) and energy efficiency. The Official Journal (OJ) of the European Union has yet to be updated to include EN 62368-1 as a standard formally associated with the Low Voltage Directive (LVD) –the LVD update is expected to be published soon.

The Low Voltage Directive (LVD) 2006/95/EC provides common broad objectives for safety regulations, so that electrical equipment approved by any EU member country will be acceptable for use in all other EU countries. The Low Voltage Directive does not supply to any specific technical standards that must be met; instead it relies on IEC technical standards to guide designers to produce safe products. Products that conform to the general principles of the Low Voltage Directive and the relevant particular safety standards include a CE marking to indicate compliance and acceptance throughout the EU.

The Low Voltage Directive version of 2014/35/EU, dated Feb. 26, 2014 was applicable from April 20, 2016. The new version aligns with the New Legislative Framework of the European Union, though actual technical requirements do not differ much from the older version. But the legal and general requirements have changed significantly (obligations of manufacturers, dealers, and marketers), and penalties are called for in the event of infringements of the directive. They must be determined by the respective Member States and should be (literally) effective, proportionate, and dissuasive.

Power ratings and no load power consumption standards for external power supplies are listed in Fig. 1. Minimum average efficiency in IV/V/VI is shown in Fig. 2. Figure 3 compares the standards for no-load power in the USA and Europe.


1. External power supply performance characteristics. (Courtesy: MEGA Electronics)


2. Minimum average efficiency in active mode. (Courtesy: MEGA Electronics)

Chronology Efficiency Standards (Mega Electronics)

In the early 1990s, it was estimated that there were more than 1 billion external power supplies active in the United States alone. The efficiency of these power supplies, mainly utilizing linear technology, could be as low as 50% and still draw power when the application was turned off or not even connected to the power supply (referred to as “no-load” condition).

Experts calculated that without efforts to increase efficiencies and reduce “no-load” power consumption, external power supplies would account for around 30% of total energy consumption in less than 20 years. In 1992, the U.S. Environmental Protection Agency started a voluntary program to promote energy efficiency and reduce pollution that eventually became the Energy Star program. However, the first mandatory regulation dictating efficiency and no-load power draw minimums wasn’t put in place until 2004. The following section traces the path from the CEC’s 2004 regulation up to the current standards that are in place today.

April 2009

Europe enacted ErPDirective 2009/125/EC (Energy Related Products) with scheduled stages of implementation for efficiency and no-load requirements equivalent to Level IV and Level V standards. The schedule defined that the EU would harmonize with Level IV efficiency standards by April 2010 and Level V efficiency standards by April 2011.

April 2011

EISA 2007, CEC Tier 3, and ErPPhase 2 took effect in full harmony of their standards, leaving us with what is now simply known as the “Level V Efficiency” standard, designated by the Roman numeral V surrounded by a circle. Level V is enforced by the agencies all over the world, except by UL in the U.S. However California also requires Level V.

April 2014

The U.S. Department of Energy (DOE) issued a pre-publication Federal Register final rule against the Notice of Proposed Rulemaking published in 2012. The new rule applies to all direct and indirect operation external power supplies (EPS), which are categorized into eight product classes. It not only increases the minimum energy efficiency requirement of EPS from level IV to level VI, but also extends their scope to encompass lower voltage AC-or DC-output EPS, multiple-voltage EPS, and EPS with nameplate output power exceeding 250 W.

Feb. 10, 2016

This is the date when the Level VI efficiency standard mandate takes effect. No-load efficiencies move down to 0.1 W for external power supplies ranging from 1 W to approximately 49 W, boost mandatory average efficiency by about 1%, and set standards for models with power ratings above 250 W for the first time.

The EPA estimates that external power supply efficiency regulations implemented over the past decade have reduced energy consumption by 32 billion kW, saving $2.5 billion annually and reducing CO2 emissions by more than 24 million tons per year. Moving beyond the mandated government regulations, many OEMs are now starting to demand “greener” power supplies as a way to differentiate their end products, driving efficiencies continually higher, and even pushing the implementation of control technologies that—in some cases—eliminate no-load power consumption altogether.

2014/6/10 Department of Energy (DoE) required manufacturers to meet Level VI two years after the final rule’s date of publication in the Federal Register (2014/2/10).

EU Code of Conduct

The European Union published its Code of Conduct (CoC) on Energy Efficiency of External Power Supplies Version 5 in October 2013. Tier 1 effectively harmonizes the EU with DoE Level VI, noting the differences in scope detailed below, and became effective as a voluntary requirement from January 2014, some two years ahead of Level VI. Its adoption as an EU Ecodesign rule is currently under review, along with the more stringent CoC Tier 2 requirement that became effective on a voluntary basis from January 2016. An official date has not been announced for these standards becoming mandatory, but many manufacturers have already begun certifying their power supplies to the tighter regulations.

The key difference between the CoC requirements and Level VI is the new 10% load measure, which imposes efficiency requirements under a low-load condition where historically most types of power supplies have been notoriously inefficient. It is important to note that CoC does not distinguish between direct and indirect operation external power adapters. While CoC Tier 1 includes the new 10% load measure, its no-load and active mode limits are less stringent than DoE Level VI.

CoC Tier 2 further tightens the no-load and active mode power consumption limits for key classes of power adapters enacted by Level VI—i.e., at output powers ≤49 W and 49 W < Pout ≤ 250 W—and covers both standard voltage and low-voltage adapters.

3. USA vs. Europe—average power in no-load mode. (Courtesy: MEGA Electronics)

Hide comments


  • Allowed HTML tags: <em> <strong> <blockquote> <br> <p>

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.