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eautocad
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Capacitor Calculation

07/11/2013 3:13 PM

how do i calculate capacitor for pf 0.7 to unity? calculations please?

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lyn
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#1

Re: capacitor calculation

07/11/2013 3:24 PM

Go to the web and open a cap. calculation site, if you are allowed to do this by your instructor.

There are about 3,140,000 results for this on Google.

We don't do homework here.
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eautocad
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#6
In reply to #1

Re: capacitor calculation

07/12/2013 12:57 AM

I want a detailed calculation on pf since am stuck out in the middle of design, i've to use a APFC relay & stages of cap's to be decided to achive , & as far as google is concerned sometimes not practical coz we need final answer. & cannot be decided on 3,140,000 results.

Every answers, every discussion, somewhere narrows towards a type of "home work" in real life, thus we share our practical expertise part.

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SolarEagle
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#2

Re: capacitor calculation

07/11/2013 3:27 PM

http://en.wikipedia.org/wiki/Power_factor

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wareagle
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#3

Re: Capacitor Calculation

07/11/2013 11:12 PM

u have not provided any information to make calculations.
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eautocad
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#4
In reply to #3

Re: Capacitor Calculation

07/12/2013 12:35 AM

3 phase, 400V

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TonyS
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#5
In reply to #4

Re: Capacitor Calculation

07/12/2013 12:55 AM

And the rest of the required data?

Don't bother giving the rest, you may as well just forget it. No one on here will do you're homework for you.

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eautocad
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#7
In reply to #5

Re: Capacitor Calculation

07/12/2013 1:10 AM

such as?

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lyn
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#12
In reply to #7

Re: Capacitor Calculation

07/12/2013 11:51 AM

There have been 3 or 4 responses here that will lead you to the desired result.

Quit asking others to do your work for you. (or, provide you with a custom tailored education, one lame question at a time).
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ffej++
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#8

Re: Capacitor Calculation

07/12/2013 2:05 AM

I'd just use a C1 capacitor.
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PWSlack
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#9

Re: Capacitor Calculation

07/12/2013 3:41 AM

Just enter "power factor correction" into the "Search all of CR4" box on the right, and click "go". It is one of CR4's most popular, and indeed tiresome, subjects.

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Nono
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#10

Re: Capacitor Calculation

07/12/2013 7:40 AM

Just read your textbook and do your homework.
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PeterT
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#11

Re: Capacitor Calculation

07/12/2013 7:52 AM

Here is a web site with a large variety of electrical and other function calculators. The FIRST ONE is a capacitor / power factor calculator. Take a look at them, and surely you will find something there.

ElectricSmarts.com calculators

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cuba_pete
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#13

Re: Capacitor Calculation

07/12/2013 1:41 PM

and

It doesn't get any easier than that!
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msamad
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#14

Re: Capacitor Calculation

07/12/2013 10:53 PM

See comment # 5 from this thread.

- MS

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rajeswari
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#15

Re: Capacitor Calculation

07/13/2013 4:33 AM

Dear eautocad,

I presume, (even though, you have not mentioned 3 phase supply) it is 3 phase Supply.

A number of times this topic discussed in this FORUM, pl. open the below link, ans you will find many many details.

http://cr4.globalspec.com/search/sitesearch?do=show&srchobjs=t%2Cc&order=asc&fs=12&sort=textmatchrank&srch=Power%20factor%20improvement

It is very simple,

RAJESWARI.D
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electricalexpert65
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#16

Re: Capacitor Calculation

07/14/2013 11:23 AM

You should multiply the total connected (operational) kW by a multiplying factor to arrive at the Capacitor kVAr required for Power Factor Improvement from an existing power factor to a desired power factor.

And, for an existing PF of 0.7 and a target PF of unity, the multiplying factor is 1.020.

Thus, if you have, say, 100kW load, then you must connect 102kVAr to improve the PF from 0.7 to Unity.
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eautocad
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#17
In reply to #16

Re: Capacitor Calculation

07/14/2013 12:53 PM

thanks electricalexpert65

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TonyS
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#18

Re: Capacitor Calculation

07/14/2013 2:09 PM

Gents,

Our friend eautocad is using this site for homework.

Look for his last topic

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eautocad
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#19
In reply to #18

oxidize

07/23/2013 1:15 AM

Don't bother sharing your knowledge, rather corroding it in the "Nut", this is not a homework for me, 100's of people are accessing this forum for information, let your "proficiency of practicality" be an information to the people who are reading. Share your knowledge...

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Users who posted comments:

cuba_pete (1); eautocad (5); electricalexpert65 (1); ffej++ (1); lyn (2); msamad (1); Nono (1); PeterT (1); PWSlack (1); rajeswari (1); SolarEagle (1); TonyS (2); wareagle (1)

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