IEC61000-4-7 Harmonic measurement standard and digital power meter age

[Kiriakos GR]

IEC61000-4-7 Testing and measurement techniques - General guide on harmonics and interharmonics measurements and instrumentation, for power systems and
equipment connected.

About this standard I care more of how this relates to instrumentation.

This standard specifies methods used in harmonic measurements.
The harmonics can be measured without grouping, with grouping and with sub-grouping.
The advantage of grouping and sub-grouping is more steady measured harmonic current values with fluctuating loads.

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Personally when i think as potential buyer of a new digital power meter (bench top),  I am trying to find a good balance between product price and my actual needs.
I am now using IEC standard release date as indication of the age that a specific digital power meter this were designed.

For example, any new instrumentation that support IEC61000-4-7 (IEC 61000-4-7:2002/AMD1:2008), this is product design of year 2008 and later.
Further note that IEEE 519-2014 makes reference to IEC 61000-4-7 and requires measurements to be made with sub-grouping.

IEC website reports, standard stability up to the year 2025.
This translates that IEC it might upgrade it or not at 2025 and later.

The advanced digital power meter is the one able to perform:
a) THD of V & I  Total Harmonic distortion.
b) Analysis of harmonic component per order, 1~50.
c)  V & I harmonic distortion percentage per order
e) V & I actual value per order   

A new question this now arises, is it worth any potential buyer to wait and see of what IEC will decides in the near future?
Another question that bothers me, this is of how much worth in cash, a newcomer digital power meter from China, which support IEC61000-4-7?

In the positive side of things, AC power meter bandwidth, this is standardized at 2022 at 2.5 kHz.

At DC power meter bandwidth, there is still an open race, and this is relative to switching frequency of diode.
Consumer level pulsing power supply they operate at 80 ~100 kHz
Fast Charging for EV this has different operating frequency.
High-End PSU for telecommunications they might have switching frequency up to 1 MHz.

For us engaging primarily with consumer level products, DC bandwidth over 300 KHz this is out of interest.   

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At another scenario, and if detailed Harmonic measurement this is not needed as requirement.
We might aim for a AC digital power meter Class 0.1
Bandwidth 2 KHZ
Which will deliver THD that we can trust, along of V,A,PF and Hz.
Such a design this is named as production line instrument.

It is unfortunate that such digital power meter, they are not coming along with PC software.
While the power meter supporting Harmonic measurement IEC61000-4-7 they do come with PC software. 

Regarding Low power measuring sensitivity, I have no problem to pair with any instrument that can measure 0.03 Watt ..  30mW and above.