2002-2021 Power energy watt-hour meters Class 1 Standards history

[Kiriakos GR]

This hunting started by me looking up for details of one misspelled electrical standard.

An Chinese brand wrote BC17215-2002 as standard in compliance of their plug-in power meter / energy / power factor.
And I found nothing about it.    
 
True standard this is GB/T 17215-2002
Alternating current static watt-hour meters for active energy(classes 1 and 2) (English Version)

This standard is only applicable to newly manufactured static active energy meters with accuracy levels 1 and 2 for measuring AC active energy in the frequency range of 45 Hz to 65 Hz and their type tests. This standard is only applicable to static active energy meters for indoor and outdoor use, which consist of a measuring piece and one or more meters installed in the same meter. It is also applicable to one or more working indicators and one or more test outputs.

GB/T 17215-2002 superseded by
GB/T 17215.321-2008 Electricity metering equipment (a.c.) - Particular requirements - Part 21: Static meters for active energy (classes 1 and 2)
GB/T 17215.322-2008 Electricity metering equipment (AC)-Particular requirements-Part 21:Static meters for active energy classes 0.2 and 0.5

GB/T 17215.321-2008 superseded by
GB/T 17215.321-2021 Electricity metering equipment (AC)-Particular requirements-Part 21:Static meters for active energy classes 1 and 2



GB/T 17215.321-2021
This defining  power meter Class standards for Classes 0.2 , 0.5 , 1.0 and 2.0


Making a Chinese product according to local standard ( UK for example) this is a need if you plan to export your technology to them. 
Unfortunately for us, technology explorers, all standards documentation this comes for a price.

In theory, all such standards for the market of Classes 0.2 , 0.5 , 1.0 and 2.0 AC power meter,  they do define measuring precision limits.
measuring precision:
AC Volts range
AC current range
Power Factor range
RMS Watt
etc etc

When such a standard gets replaced by a new, the new its more strict.
Newly developed electronics needed, for the production of fresher measuring instruments.
All products made due the old standard, they cannot be imported any more at the specific country.

Oldest found standard this is GB/T 17215-1998

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About GB/T 17215-2002
I am aware of acceptable limits for 10A shunt.

Example:
product of Class 1.0
Active Power / Accuracy Class
0.2 ~ 1 W  /  Less than 10% ( + / - )
1 ~ 5 W    / Class 5.0 ( 5 %) 
5 ~ 2200 W / Class 1.0 (1%)

RMS Current:
20mA ~ 10 Arms / Class 1

Power Factor  /  Class 1
For : 0.2 ~ 5 W       Even or greater than 0.030 PF
For : 5 ~ 10 W        Even or lower than 0.030 PF
For : 10 ~ 2200 W  Even or lower than 0.010 PF


By combining all the above information's, the specific Class 1 instrument, behaves as Class 1.0 only when our measuring current this is 20mA as minimum.
Then we check Watt power reading.
Final step, we do an inspection if Watt Power and Power Factor are both high enough (among  limits ), and then we trust the measurement. 
      
Practical example for Class 1.0 (The load it should be minimum 5W)
Current consumption minimum is 20mA
Volts AC 230
Power Factor 1.0
Total 4.6W = Pass

Another Example 

Current consumption minimum 20mA
Volts AC 230
Power Factor 0.030 
Total  138 mW = Fail Because its under Watt minimum measuring value.



In conclusion,  we need to separate in our head the description as measuring ability and the description of accuracy.
While Watt range might be from 0.2 W and up to 2200W,  only when we are within in range of Power Factor that our instrument is capable to measure accurately, then we may trust the measurement.
For measuring Low power (standby power),  the more accurate in Power Factor measuring instrument, this will be the winner.
An instrument with four digits Power Factor its a good start so to be called as modern. 
 
The specific product example with 10A shunt it qualify to measure pulsing power supply only in the range of 5 ~ 2200 W.
This is named as power consumption measurement, but this is nowhere near to Power Standby measurement expectations. 
Class 10 instrument, its 10% Error at 0.2 ~ 1 W
Class 5 instrument, its 5% Error at 1 ~ 5 W

[Kiriakos GR]

Further research of electrical standards documentation, this helped me to understand that GB/T xxxxxx standard this is Chinese applicable standard.
But even so, the source this is always IEC organization.
The Chinese version of a electrical standard, it is offered in the Chinese language primarily, and this fights back any language barrier problems.

For example GB/T 17215-2002 this is actually IEC1036-2000
The source of this information, this is National Institute of Metrology of China.

First logical conclusion, specific IEC Standard, this were applicable in China with two years of delay.

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This rabbit hole has a huge depth, at the year 2007 National Institute of Metrology of China,  organized a seminar for Chinese industries that wish to engage at the manufacturing of AC power meter.
They did illustrate their own testing system, the standard system for calibration inspection of AC power meter. 
Name: Electric energy and Power Laboratory 
Model : YES-10000 Class 0.01 three-phase electric energy standard device

For the development of this test system, they had use previously several high precision multimeter of that era,  Solatron Instruments / Schlumberger  from UK.
And even HP 3458A ( Agilent / Keysight).

And for AC loads for calibration inspection, they use the help of Radian Research, Inc. ( USA ). 
https://www.radianresearch.com/EOS_RD3X.html