There are many ways to measure AC voltages.  The most common is RMS
which is the usual 220VAC (110VAC USA).  RSM voltage is litterally "Root
Mean Square", so you square your readings, average them over one cycle,
and take the square root.  It would help if you could sync your readings
to the zero crossings of the power line.

Sherpa Doug

> -----Original Message-----
> From: Tony Pan [mailto:weidong.pan@VERIZON.NET]
> Sent: Wednesday, February 27, 2002 9:56 AM
> To: PICLIST@MITVMA.MIT.EDU
> Subject: [pic] Math Question - Measuring AC Voltage
>
>
> Hi,
>
> I want to use a pic to measure AC line voltage. First, my
> hardware scales
> down 200V to 5V and flips the negative duty cycle to positive
> so that the
> pic can read the signal. Then the pic reads the voltage every
> 0.1ms with an
> adc port. Now I have many almost 100 reads within a duty
> cycle. No this is a
> math question: How do I calculate the AC voltage from these reads?
>
> Thanks,
> Tony
>
> --
> http://www.piclist.com hint: The list server can filter out subtopics
> (like ads or off topics) for you. See http://www.piclist.com/#topics
>
>
>

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics