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impedance calculation - Power Factor

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impedance calculation - Power Factor

Postby NathanUnger » Thu Jan 21, 2016 4:00 am

Hello,
I'm working with a 12 volt AC signal. I have the Voltage on channel A and the TA018 current clamp on channel B
I would like to calculate the impedance using a math channel A/B, and a measurement, but where the current goes through zero, the signal goes out of range. How do I get around this problem?
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Re: impedance calculation

Postby AndrewA » Thu Jan 28, 2016 1:24 pm

Hi,
I agree, so you want the AC rms value of the impedance? Do also want the reactance and true resistance of circuit as well as phase angle?
See diagram-
http://www.nap.edu/openbook/0309057973/ ... 170001.jpg
Regards Andrew
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Re: impedance calculation

Postby NathanUnger » Thu Jan 28, 2016 3:56 pm

Hello,

Thanks for your reply and the diagram.

Of course, the more information I can get, the better, but I don't actually need more than just the AC rms impedance value because I am only making comparison measurements to a "known good" value. I thought there might be some mathematical technique or connection methodology to get around the problem right within Picoscope.
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Re: impedance calculation - Power Factor

Postby AndrewA » Tue Feb 02, 2016 11:57 am

Hello,

Most of the calculations cannot be done in PicoScope. But the measurements needed can be exported out. And could be easily be done in excel.
See this post on exporting measurement values-
https://www.picotech.com/support/topic15481.html?hilit=batch
First you need to setup your channels and the measurements needed-
See the screen shot and example psdata file with-

-Channel A for- Volts
-Channel B for- Amps
-Maths channel - ChA x ChB (Instantaneous Power)


The measurements that are exported are-
Volts- rms
Current(Amps) - rms
Apparent Power which is the DC average of Instantaneous Power (Volts x Amps)


The attachment AC vectors and Power factors.psdata is no longer available

Now follow the calculations in the attached pdf.
AC Vectors and Power Factor.pdf
AC vectors and Power Factor cals
(293.94 KiB) Downloaded 12 times

Here is Excel file with the calculations included-
Factor factor.xls
Excel calculations
(39 KiB) Downloaded 5 times

I have not used complex numbers but you could do for some of the calculations.
Attachments
AC vectors and Power factors.psdata
AC vectors and Power Factor
(1.03 MiB) Downloaded 51 times
Regards Andrew
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