wiz-icon
MyQuestionIcon
MyQuestionIcon
6
You visited us 6 times! Enjoying our articles? Unlock Full Access!
Question

The two-wattmeter method is used to measure power in a balanced 3-phase circuit, drawing lagging current. The power factor, if one of the wattmeter reads zero is

A
0.5
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
0.8
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
1.0
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
0.0
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is A 0.5
Power factor=cos ϕ

=cos tan13(W1W2)(W1+W2)

When one of the two wattmeters reads zero.

i.e. say W2=0

then,
cos ϕ=cos tan13(W10)(W1+0)

=cos tan1 3

=cos tan1(1.73)=0.5

flag
Suggest Corrections
thumbs-up
8
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Three Phase Two Wattmeter Method-2
MEASUREMENT
Watch in App
Join BYJU'S Learning Program
CrossIcon