Power Factor

[huynhngochoi]

Hi,

I am using the PM8000 meter and encountering the following issue. The total Apparent Power of the 3 phases is 118.67, but the meter displays 105.789. Similarly, Active Power and Reactive Power are also displaying inaccuracies. Does anyone know why this is happening?

Thank you.

[Charles_Murison · Accepted solution]

Hello @huynhngochoi 

Given the numbers you are seeing the numbers reported by the meter look correct to me.

In the ION meters there is 2 methods for calculating kVA,
Vector Sum or Scaler Sum, Vector Sum you can think of as using the total kW and KVAR to get kVA. Scaler Sum you can thank of as adding individual phases. Math may not be exactly that but close enough approximation.

Total
kW: 35.855 + 34.825 + 34.763 = 105.443
kVAR: -2.797 -2.757-2.994 = -8.548
kVA: (105.443^2+(-8.548(^2)^0.5 = 105.788
105.433/105.789 = 99.66%

Phase A
35.855/40.383 = 88.7873
repeat for phase B and C the number match the diagram.

Regards,

Charles

[huynhngochoi]

Thanks for your support.