Question

still looking for help with :
a single phase circuit has a phase angle of 60 degrees between the current and the voltage. How do I calculate the power factor?
I know that the power factor = cosq.... but i dont know how to use the equation.
Can anyone help please?

Answer 1

Power factor equals cosine of the phase angle between voltage and current.

Answer 2

thanks Radar..............but what does that mean????

Answer 3

In this case .5 (a very bad power factor)
PF=cos60
PF=.5

Answer 4

It means that the actual power is less than the apparent power. Other words in this case half the power is real and half is unreal.

Answer 5

Usually it is inductive loads, primarily motors that creates this power factor by introducing a lag in current with reference to voltage. It is then corrected by a capacitance bank. Even if it is not totally real, all current carrying conductors have to have the capacity to handle it.

Answer 6

I really appreciate your help radar. thanks.

Answer 7

No problem, if you draw the sine wave of the voltage leading the sine wave of the current, only when both current and voltage wave form have the same polarity does actual power is produced. For some reason I don't have the "draw" box showing or IO would draw a picture lol. But I think you could draw it and see what I mean.

Answer 8

i will give it a try, thanks again.

Answer 9

Good luck, you are studying a good field.

Answer 10

When both current and voltage are above the line or below the line at the same time will power (real) be created (when opposite, one above the other below at the same time unreal power)