Question

Wattmeters are compensated for errors due to inductance by _________

(a) using a series capacitor

(b) using a parallel capacitor

(c) using a series resistance

(d) using a parallel resistance

I have been asked this question in my homework.

This key question is from Errors in Dynamometer Wattmeter topic in division Measurement of Power and Related Parameters of Electrical Measurements

Answer 1

Correct choice is (b) using a parallel capacitor

To explain I would say: Wattmeters are compensated for errors caused by the inductance of pressure coil through the connection of a suitable parallel capacitor with multiplier resistance R.

Fig illustrates that the total impedance of the pressure coil circuit Z2 equals the total resistance of the pressure coil circuit namely R2.