AS NZS 62087.1:2010 – Power consumption of audio, video and related equipment Part 1: Methods of measurement.
5 General method of measurement
5.1 General measuring conditions
5.1.1 Power supply
Measurements shall be carried out using a power supply providing the nominal voltage and frequency of the region. The voltage and frequency used during the power measurement shall be described in the report.
The fluctuation of the voltage supplied during the tests shall not exceed ±2 %. The frequency fluctuation and the harmonic components of the supplied power shall not exceed ±2 % and 5 % respectively.
5.1.2 EnvIronmental conditions
Ambient temperature 15 °C to 35 °C, preferably 20 °C, unless otherwise specified in this standard. The ambient temperature shall be described in the report.
5.1.3 Adjustment of controls
The controls not specifically mentioned in this standard shall be in the position adjusted by the manufacturer for shipment to the end user. These controls shall remain in this state for the duration of the test.
5.1.4 Input signals
For equipment for which the input signals are not explicitly described in this standard, the nominal signals as specified by the manufacturer shall be applied during the test. The input signals used shall be described in the report.
5.1.5 Power Measurement Instrument
The measurement shall be carried out directly by means of a wattmeter, a wattmeter with averaging function, or a watthour meter by dividing the reading by the measuring time. For television sets, in the case that the input video signal varies over time, a wattmeter without an averaging function shall not be used to carry out the measurement.
The sampling rate of the watthour meter or wattmeter with averaging function should be high enough to achieve an accurate measurement.
The power measurement instrument used shall measure the real power consumed regardless of the power factor of the device under test.
Measurements of power of 0,5 W or greater shall be made with an uncertainty of less than or equal to 2 % at the 95 % confidence level. Measurements of power of less than 0,5 W shall be made with an uncertainty of less than or equal to 0,01 W at the 95 % confidence level. The power measurement instrument shall have a resolution of:
— 0,01 W or better for power measurements of 10 W or less;
— 0,1 W or better for power measurements of greater than 10 W up to 100 W;
— I W or better for power measurements of greater than 100 W.
For equipment connected to more than one phase, the power measurement instrument shall be equipped to measure total power of all phases connected.
NOTE 1 In the case of standby mode power measurement, It should be ascertained that the wattmeter or the watthour meter is suitable to measure the power consumption of power supplies working in a burst mode with a low duty cycle and the low power consumption levels in the standby modes.
NOTE 2 For digital power meters a sampling rate of at least 10 kHz is recommended. (Sampling rat& in many specifications refers to how often the display is updated, and not the actual sampling frequency of the input waveform.) Most digital power meters are believed to meet this requirement. If it Is not listed In the manufacturer’s specifications, contact the manufacturer.
NOTE 3 For more information about the determination of uncertainty of measurement, refer to IEC 62301: 2005, Annex 0.
5.2 General measurement procedure
The following measurement procedure shall be used, unless otherwise specified in this standard.
Measure the power consumption of the appliance at a time not less than 15 minutes after it has been switched into the relevant operating mode.
If the power consumption in a certain operating mode has more than one stable level, the measuring time shall be of an appropriate duration to measure the correct average value.
Some appliances switch, after a time delay, from a standby mode to a mode with a lower (or zero) power consumption. The power consumption before and after the switching shall be determined.
For equipment with less functionality than described, for example playback tape equipment, only the relevant parts of the measuring conditions have to be considered.
The results shall be given in watts (W), with a number of relevant digits in accordance with the accuracy of the measurement.
NOTE If In the measuring conditions, the standby mode Is mentioned without further specification, the standby modes as defined in clause 4 are referred to.
6 Measuring conditions for television sets, excluding On (average) mode.