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IEC TR 63079: Audio/Video and ICT Equipment — Energy Efficiency Measurement Methods
Technical Report on Standardized Energy Performance Testing for Connected Electronic Devices
1. Scope and Measurement Framework of IEC TR 63079
IEC TR 63079 addresses a critical gap in energy efficiency regulation: the absence of a harmonized measurement methodology for the diverse and rapidly evolving landscape of audio/video (AV) and information and communication technology (ICT) equipment. While individual product categories have long been covered by regional regulations such as the EU Ecodesign Directive (EuP/EcoDesign) and ENERGY STAR programs, the measurement approaches varied significantly, making cross-category comparison impossible and creating compliance burdens for manufacturers selling globally.
The proliferation of “always-connected” devices — smart speakers, streaming media players, network-attached storage, video doorbells — has created a new energy consumption category: network standby. IEC TR 63079 reports that network standby can account for 40-70% of a device’s total annual energy consumption, yet prior to this report there was no internationally agreed measurement method for this mode.
The report establishes a four-mode measurement taxonomy: Off Mode (device connected to mains but not performing any function), Network Standby (device is not in active use but maintains network connectivity and can resume functions on receipt of a network command), Idle/Sleep Mode (device is operational but not performing its primary function), and Active Mode (device is performing its primary function under defined load conditions). Each mode has specific measurement duration requirements, stabilization criteria, and power quality conditions.
| Operating Mode | Measurement Duration | Stability Criterion | Typical Power (55″ TV) | Typical Power (Home Router) |
|---|---|---|---|---|
| Off Mode | 10 minutes | ±1% over 5 min | <0.5 W | <0.3 W |
| Network Standby | 30 minutes | ±2% over 15 min | 1.5-3.0 W | 4-8 W |
| Idle/Sleep | 20 minutes | ±2% over 10 min | 40-80 W | N/A |
| Active Mode | 60 minutes | ±5% over 30 min | 80-200 W | 6-15 W |
2. Measurement Methodology and Instrumentation Requirements
IEC TR 63079 specifies stringent requirements for the measurement instrumentation. Power measurements must be made using a wideband power analyzer with a minimum sampling rate of 1 MS/s and a bandwidth of at least 100 kHz to accurately capture the harmonic content of modern switch-mode power supplies. The report mandates that the measurement instrument must have a crest factor capability of at least 3:1 at rated range, as the peak-to-average ratio of modern ICT device current draw can exceed 2.5:1 due to burst-mode operation in standby and pulsed load patterns in active mode.
A particularly important specification is the reference test signal for active mode measurements. For audio devices, the report defines a pink noise signal shaped to the ITU-R BS.1770 weighting curve with an average level of -20 dBFS. For video devices, a 16-step grayscale ramp pattern at 50% average picture level (APL) is specified. These signals represent realistic use cases while providing reproducible measurement conditions across different laboratories.
The report also addresses the challenge of measuring devices with adaptive power management — modern ICT equipment that dynamically adjusts processing performance based on workload. The measurement protocol requires a “stabilized active” measurement after a 30-minute warm-up period with the device performing its most common task (e.g., 4K video streaming for a smart TV, VoIP call for a desktop phone). The average power over the final 30 minutes of the 60-minute measurement window is reported as the active mode power.
Network standby measurement is uniquely challenging because the power consumption depends on both the network protocol (Ethernet, Wi-Fi, Zigbee, Thread) and the network traffic condition. IEC TR 63079 defines three sub-modes: NS-1 (network interface active, no data traffic), NS-2 (network interface active with periodic keep-alive traffic), and NS-3 (network interface active with presence of a companion device or cloud service). Measurements must be performed in all three sub-modes, with the weighted average reported using a formula that reflects typical usage patterns.
3. Engineering Design Insights for Energy-Efficient AV/ICT Equipment
One of the most effective design strategies documented in IEC TR 63079 is the use of gallium nitride (GaN) power semiconductors in the AC-DC conversion stage. GaN FETs operating at 300-500 kHz switching frequency (versus 65-100 kHz for silicon MOSFETs) can reduce standby power by 40-60% while maintaining active-mode efficiency above 94%. The higher switching frequency also allows for smaller magnetic components, reducing overall device weight and material cost.
Power supply architecture selection: The report compares three approaches: (1) single-stage flyback converters (lowest cost, moderate efficiency, 70-85%), (2) two-stage PFC+LLC resonant converters (higher cost, excellent efficiency >92%), and (3) active-clamp flyback with GaN (best efficiency >94% across load range, moderate cost). For typical home gateway devices operating mostly in standby or low-load conditions, the active-clamp flyback with burst-mode control achieves the best annual energy consumption despite a higher component cost.
Network interface power management: IEC TR 63079 provides specific guidance on reducing network standby power. Energy-Efficient Ethernet (EEE) per IEEE 802.3az can reduce 1 GbE PHY power from 1.2 W to 0.15 W during idle periods. However, the report warns that many implementations fail to properly enter the low-power idle (LPI) state because upper-layer protocol keep-alive intervals are shorter than the LPI wake-up time. A design recommendation is to buffer keep-alive packets at the MAC layer and send them in bursts, allowing the PHY to remain in LPI for at least 90% of the time.
A common pitfall identified in the report is the USB charging penalty: devices that provide USB host ports for media playback or maintenance access often draw 2-5 W continuously to keep the USB controller and 5 V rail active, even when no USB device is connected. The report recommends implementing USB port power gating with presence detection that disables the 5 V rail when no device is detected for more than 5 minutes, recovering 15-40 kWh annually per device.
4. Frequently Asked Questions
Q1: How does IEC TR 63079 relate to the EU Ecodesign Directive requirements?
A: IEC TR 63079 provides the measurement methodology that underpins the energy efficiency requirements of the EU Ecodesign Directive for electronic displays, network standby, and external power supplies. Compliance testing for CE marking uses the methods defined in this report.
A: IEC TR 63079 provides the measurement methodology that underpins the energy efficiency requirements of the EU Ecodesign Directive for electronic displays, network standby, and external power supplies. Compliance testing for CE marking uses the methods defined in this report.
Q2: What is the single most impactful design change to improve energy efficiency in consumer AV equipment?
A: Implementing a dedicated always-on low-power processor (such as a Cortex-M4 running at 32 kHz) to handle network connectivity and wake-up logic, allowing the main SoC to remain completely powered off during standby, can reduce standby power from 3-5 W to below 0.5 W.
A: Implementing a dedicated always-on low-power processor (such as a Cortex-M4 running at 32 kHz) to handle network connectivity and wake-up logic, allowing the main SoC to remain completely powered off during standby, can reduce standby power from 3-5 W to below 0.5 W.
Q3: Are there special considerations for PoE (Power over Ethernet) powered devices?
A: Yes. For PoE-powered equipment, the measurement must account for power losses in the PSE (power sourcing equipment) and the cable. IEC TR 63079 specifies that efficiency be measured at the PSE output rather than the PD input, and the report provides a cable loss correction table for various cable lengths.
A: Yes. For PoE-powered equipment, the measurement must account for power losses in the PSE (power sourcing equipment) and the cable. IEC TR 63079 specifies that efficiency be measured at the PSE output rather than the PD input, and the report provides a cable loss correction table for various cable lengths.
Q4: How does the report handle devices with battery chargers?
A: The report distinguishes between the charging function (measured using a standardized discharge-charge cycle) and the device’s own operating modes. The energy consumption of the charging function is reported separately from the device’s active/standby energy consumption.
A: The report distinguishes between the charging function (measured using a standardized discharge-charge cycle) and the device’s own operating modes. The energy consumption of the charging function is reported separately from the device’s active/standby energy consumption.
