Current transformer polarity and power flow

[adool_617]

Hello

i need to know , does the polarity of the current transformer affects the power measurements in AC systems, and if it does , how it affects the power measurements knowing that in measuring power we use the RMS values

anybody have any idea about this ??

that's to say , if you have a 2000 Amps line and it is three phase line

you connect 3 CTs on each phase ratio 2000/5 then you connect the CT to ammeter which is calibrated to give full scale (2000A) at 5 A

if we connect a KWH meter instead of the ammeter , is polarity important ?

 

[anorlunda]

Sure it's important. A watt meter can measure power in both directions. We arbitrarily set one direction as positive, and the other negative.