Internationally aligned test standards for televisions
Provided by Steve Pantano
In the last decade, televisions have undergone a radical change with the demise of cathode ray tube (CRT) technology and the rapid uptake of plasma, then liquid crystal display (LCD) technologies. There have also been significant developments in back lighting for LCD TVs, with light emitting diodes (LED) now commonplace in many markets and organic light emitting diodes (OLED) coming to the mass market soon. Televisions currently account for an estimated 3 to 8% of global residential energy use, so the uptake of more efficient televisions would benefit consumers through lower energy bills.
The rapid stock growth, fast-moving technology developments, and competitive price pressures mean that televisions are a product area both challenging and crucial for energy efficiency policy-makers. However, the homogeneity of the global market means this is also an area where the harmonisation of test methodologies, and even performance levels, could be made a reality within a few years if the necessary decision-makers are engaged in the process and if improvements are made to existing technical standards. Harmonised test methodologies for products provide the foundation for internationally comparable energy performance benchmarks that can be used by governments to design policies with performance thresholds that are appropriate to their own market and economy. If different television energy consumption methods are used for different programmes, then it is more difficult to conduct programme comparisons.
Although test procedures for televisions can vary by country, they either directly adopt or partly reference (with regional variations) the following two IEC standards:
- IEC 62087 Ed. 3 and Ed. 2 – Methods of measurement for the power consumption of audio, video and related equipment; and
- IEC 62301 Ed. 2.0 2011 – Household electrical appliances – Measurement of standby power, which addresses standby testing for a broad selection of products, without specific reference to televisions.
While test procedures do vary, they generally all rely on some fundamentals from the IEC 62087 test methodology. However, there are still significant differences in implementation across various national regulatory and voluntary programmes, for example:
- Despite the use of a harmonized video test loop with an average picture level (APL) representative of worldwide broadcasting (to which average power demand is proportional), recent developments in technology such as 3D capability are beyond the reach of the current test method.
- A primary weakness in all the current test standards is that luminance needs to be tested, set and declared in some way, and this is prone to errors, particularly where this variable is tied to the efficiency metric.
- The Chinese test method uses a luminance based energy performance metric (emitted luminance per Watt) whilst most other countries use an energy performance metric based on screen area (Watts per square centimeter).
These differences should ideally be resolved to send clear, consistent and effective messages both to product designers and to consumers.
There are multiple reasons why different regions use the IEC 62087 test procedure in different ways. In some cases, regions use technical studies to inform the approach they should take and these studies sometimes bring new information to light that has not been considered in the IEC 62087 test procedure. Regional variations are not likely to be due to testing laboratory facilities or due to the cost of burden of testing, as there is generally a great deal of consistency in laboratory set-up between countries, both in terms of capability and capacity. Most test laboratories employ the same equipment and have well-trained staff. Where variation does occur between laboratories, this is usually due to different interpretations of the test standard by the laboratory staff.
The IEC 62087 Standard is currently undergoing a revision which is due to be finalized and published this year. The APEC Collaborative Assessment of Standards and Testing (CAST) programme is currently working on "Internationally Aligned Test Methods and Performance Requirements for Televisions", which will propose recommendations to the next revision of IEC 62087 (likely in 2016) and to the development of policy measures within the APEC economies.
Navigation and communications
Rapidly evolving and highly regulated
Measuring energy performance
Dependent on electric and electronic components
Cutting across many different industry sectors
Protection from interference
Electrical equipment and systems for railways
Safety, security and the environment
Power consumption tests