Energy Measurements In Harmonic Environment

Yes.

They only measure resistive power.

Dear Sir,

Thank you very much for your prompt reply. Further to your answer I would like to know whether the disc type energy meters can measure the energy in harmonic fregeuncies likes of 3rd, 5th ..etc inaddition to fundamental frequency.

The mechanical drive rotating the disc-which is driving the VEEDER -ROOT type decimaL totalizer readout is a single phase AC motor.

Linear till saturation sets in- but is fundamentally rotating at speed directly proportional to V.I.cosφ

V and I being assumed pure sinusoidal--i.e. without any harmonics. And V is assumed varying (good for customer ).

How nearly correct the shown readout will be in presence what% of harmonics- will need huge computation. The Supply company may lose or the Customer might.

That is why the thrust now is on to install accurate Computer-like Analog/digital chips which claim Near-perfect readouts -in presence of harmonics-because this chip does not assume Sinusoidal 50/60Hz.

Read this from Analog Devices:

The ADE7752B* is a high accuracy polyphase electrical energy measurement IC. The ADE7752B specifications surpass the accuracy requirements as quoted in the IEC62053-21 standard. The only analog circuitry used in the ADE7752B is in the analog-to-digital converters (ADCs) and reference circuit. All other signal processing (for example, multiplication, filtering, and summation) is carried out in the digital domain. This approach provides superior stability and accuracy over extremes in environmental conditions and over time.

And can you believe-they can sell each chip @$2.29 !

Dear Sir,

Thank you very much for your comprehensive reply.