Hi Mohamed,

How much current will your power factor meter have to handle?

There are standard shunts available (small value power resistors) which
have a very accurate resistance and develop a small but certain amount of
voltage across them in proportion to the current going through them. You
can then amplify this voltage with an op amp and detect its zero crossing,
as well. However, in order to choose the right kind of shunt, you have to
know how much current it needs to handle.

Sean


At 10:55 PM 2/7/99 +0200, you wrote:
>Hi
>I want to use PIC16F84 to measure power factor witch is (as I know ) the
>angle between
>voltage and current. I know how to detect voltage angle (zero crossing ) but
>how to do it for the current should I use current transformer? any other
>idea.
>
>Thanks in advance
>
|
| Sean Breheny
| Amateur Radio Callsign: KA3YXM
| Electrical Engineering Student
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