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Participant

Join Date: Jan 2013
Posts: 3

Ratio Error Measurement Algorithm For CT Using Microcontroller

01/02/2013 1:42 AM

Dear Sir,

we are leading electrical manufacturing company, and I have assigned a task to design CT/PT testing unit which will measure the ratio and phase error of the TEST CT against REFERENCE CT. I can able to take the true RMS samples of reference as well as test CT, however no idea about ratio error calculation algorithm. Anyone can guide me for ratio error measurement calculation formula / algorithm based on reference CT?

Thanks in advance.

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Guru
United Kingdom - Member - Indeterminate Engineering Fields - Control Engineering - New Member

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Location: In the bothy, 7 chains down the line from Dodman's Lane level crossing, in the nation formerly known as Great Britain. Kettle's on.
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#1

Re: Ratio error measurement algorithm for CT using microcontroller

01/02/2013 7:14 AM

That a <...leading electrical manufacturing company...> should need to resort to global internet anonymous engineering forums like CR4 to help with the design of its products is quite bizarre.

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Guru

Join Date: Oct 2008
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#2
In reply to #1

Re: Ratio error measurement algorithm for CT using microcontroller

01/02/2013 8:46 AM

Seems to be more and more the norm.

Sadly, the poor souls asking for help, don't realize the risks of accepting technical advice from total strangers.

Application of Chaotic Optimization Algorithm for ...

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Guru
Engineering Fields - Power Engineering - New Member

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#3
In reply to #2

Re: Ratio error measurement algorithm for CT using microcontroller

01/02/2013 10:32 PM

..but the good part is that these (im)posters' names are forever inscribed on the web for anybody (like his boss or client) to see through a simple search on his/her name.

Perhaps once they realize this the number of these questions will go down, or the number of Anonymous Postings will go up, but not answered.

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Participant

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#4
In reply to #2

Re: Ratio error measurement algorithm for CT using microcontroller

01/02/2013 11:05 PM

Dear Sir,

Expecting co-operation from such a narrow minded people is my big mistake. Thnks

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Guru

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#6
In reply to #4

Re: Ratio error measurement algorithm for CT using microcontroller

01/02/2013 11:38 PM

If you want cooperation, buy it.

If you pay someone who is competent, they will know, "about ratio error calculation algorithm".

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Participant

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Posts: 3
#5
In reply to #1

Re: Ratio error measurement algorithm for CT using microcontroller

01/02/2013 11:08 PM

Dear Sir,

Expecting co-operation from such narrow mided people is my big mistake, i am really depressed due to such reply of such prestigious (un)professionals.

Thanks

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Guru
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#7
In reply to #5

Re: Ratio error measurement algorithm for CT using microcontroller

01/03/2013 7:43 AM

Please consult this site for your depression. If your depression is about taking on a job that you are not qualified to do and expecting others to do it for you for free, go here.

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#8

Re: Ratio Error Measurement Algorithm For CT Using Microcontroller

01/04/2013 11:30 PM

I am truly sorry for the actions my esteemed colleges have presented here. But, I must also tell you that finding the information your seeking is very easily completed without asking a site like this to answer the problem. I have worked many days solving issues that come before me, like most of the others here have, on our own. Do we get way too many request for information or answers to questions someone should have worked out on their own, Yes! So bear with us, as on occasion we go off on the deep end and say things that are not, maybe quite the right way of handling the issue.

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#9
In reply to #8

Re: Ratio Error Measurement Algorithm For CT Using Microcontroller

01/05/2013 8:40 AM

FixIt, OP received the responses because of his statement "... however (I have) no idea about ratio error calculation algorithm. Anyone can guide me..." which indicates that he did not take the first step to solving his own problem and was instead expecting others to do his work for him.

Had his posting been something like "...I just finished reading two articles from the IEEE which have algorithms that yield differing results when applied to the same problem...", or something that indicated some effort of his own, then the responses may have been entirely different.

If you wish to do other peoples' work for them then feel free to do so, but I do note that you did not provide the "...very easily completed..." source. I for one, would like to know what it is so that I can compare it with the link provided by lyn and others that were found by Googling.

One more thing, please stick to making excuses for your own behavior, neither you nor I have any way of knowing the motivation for any particular posting; all due diligence lies with the reader.

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#10

Re: Ratio Error Measurement Algorithm For CT Using Microcontroller

01/06/2013 7:50 PM

Your measurement device will have to have complex math capability. The result should include real and imaginary components. Such instruments can easily measure the ensemble average of hundreds of samples for both the reference transformer and the test transformer. These instruments are typically called "digital signal analysers" (and use the FFT for such calculations).

I am unaware of a specific algorithm for your application, but the complex ratio of those two tests should yield the desired result. You might explore the process on such an instrument called the "frequency response function", which is exactly the complex ratio of the two signals. You could excite both units with the same test signal and capture the output of both units simultaneously on channels 1 and 2. This result is expressed as R + jI, but can easily be plotted as Magnitude and Phase.

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Users who posted comments:

fixitorelse (1); lyn (2); p_kiran76 (2); PWSlack (1); RAMConsult (3); WoodwardDL (1)

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