【PM8000】Current and voltage measurement accuracy

Miyai · ‎2022-08-24

Hello,

I would like some advice on how to think about accuracy.

The manual described IEC 61557-12 Class 0.2 for current and voltage.

I checked IEC 61557-12 and confirmed the accuracy is ±0.2%.

What is the “standard value” for this ±0.2%?

My guess is that the reference value is “Imax”.

In the case of PM8000, should Imax be 10A?

Best regards,

Miyai

DanL · ‎2022-08-25

Correct. The IEC61557-12 standard requires (Table 22) current measurement uncertainty (for transformer connected circuits) to be specified as a percent of reading over the range from 10% In (10% of 5A = 50mA) to Imax (10A).

See Answer In Context

Charles_Murison · ‎2022-08-25

Hello @Miyai

When the accuracy is ±0.2%, this is relative to the measurement itself. If you input was 1.250 A, the meter would measure between 1.2525 A and 1.2475. If input was 2.500A, the meter would measure between 2.505 A and 2.495 A.

Regards,

Charles

L4 Prime for Advanced metering and Utilities

DanL · ‎2022-08-25

Correct. The IEC61557-12 standard requires (Table 22) current measurement uncertainty (for transformer connected circuits) to be specified as a percent of reading over the range from 10% In (10% of 5A = 50mA) to Imax (10A).

Miyai · ‎2022-08-25

Hello @DanL , @Charles_Murison

Thank you for the advice.

I will check the IEC standard again.

Best regards,

Miyai