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howrang bajaj
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Join Date: Aug 2008
Posts: 22

Microfaraday Capacitors: Fan Windings and Speeds

08/16/2008 3:14 AM
question -A 60 W Fan fitted with 2.5 microfarady capacitor.find out the current flowing in fan winding,if fan is connected to
230 V , 50Hz.
I got 0.2612 A
now question is : if you connect 1.5 microfarady capacitor instead of 2.5 microfarady then what will happen to the fan winding & speed.
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Sparkstation
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#1

Re: electrical

08/16/2008 5:36 AM

Hello howrang bajaj

You are the first person ever, who has written about microfady capacitors.

Kind Regards....

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howrang bajaj
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#3
In reply to #1

Re: electrical

08/16/2008 8:46 AM

i m really sorry for that spelling.

but sir i have not recieved answer
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HoleInTheSnow
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#8
In reply to #1

Re: electrical

08/17/2008 11:28 AM

Sparkstation, give the guy/girl a break. He/she just asked a question and has made a spelling mistake. We all knew what was meant so why be petty about it.

Kind Regards

Mr. WA Snow
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Sparkstation
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#12
In reply to #8

Re: electrical

08/18/2008 6:17 AM

Hello HoleInTheSnow

C'mon too, please.

Please note that in my earlier reply:http://cr4.globalspec.com/comment/267495/Re-electrical

Did you notice my deliberate spelling error = the word in bold type?

Kind Regards....

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electrone
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#2

Re: Microfaraday Capacitors: Fan Windings and Speeds

08/16/2008 7:48 AM

If you hook up a smaller capacitor like 1.5 microfarads instead of 2.5, I think the most likely result is that your motor will turn slower with less power output and maybe less efficiency.
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Mark684
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#4

Re: Microfaraday Capacitors: Fan Windings and Speeds

08/16/2008 5:42 PM

You have really got to start doing your OWN homework.

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Sparkstation
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#5
In reply to #4

Re: Microfaraday Capacitors: Fan Windings and Speeds

08/16/2008 7:24 PM

Hello Mark684

from me

Kind Regards....

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YWROADRUNNER
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#6

Re: Microfaraday Capacitors: Fan Windings and Speeds

08/17/2008 12:06 AM

I agree with Mark 684, however a good place to start in answering your own question would be to look up the formula for capacitive reactance, you might also want to consider the effect a different size capacitor will have on the phase angle of the motor winding it is in series with. Lastly if this not be a homework question you are exceeding the recommended percentage change in capacitance from the OEM specified run capacitor.

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gadgetman
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#7

Re: Microfaraday Capacitors: Fan Windings and Speeds

08/17/2008 1:42 AM

TRY IT!. you didn't emphasize any difficulty using a 2.5 micro (as in 10E-6) farad (as in unit of capacitance) cap, It will be just as easly to measure current with another capacitor, and you will notice if it's faster, the same, or slower speed. It should be easier than posting the question here, anyway; you were right there - meter in hand - did you get scared? did your mommy take your test leads away ? why would you not just hook it up and SEE?!?

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howrang bajaj
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#10
In reply to #7

Re: Microfaraday Capacitors: Fan Windings and Speeds

08/17/2008 1:57 PM

N=(V-IR)*60A/(Z*q*P)

N=rpm

V=applied voltage

I=Fan current

R=winding resistace

A=no. of parallel path

Z=no. of turns

q=flux/pole

p=no. of poles

so if i m using 1.5 capacitor the current (I) will reduce then speed must increase.

i m afraid in doing wrong because if somthing goes wrong then i will have to pay for that.

thank you.
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bluezone
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Join Date: Jan 2008
Location: Tulsa, OK
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Good Answers: 1
#13
In reply to #7

Re: Microfaraday Capacitors: Fan Windings and Speeds

08/19/2008 11:38 AM

I agree with Hole in the Snow. What's with everyone? Calm down everybody! If you don't agree with something, just don't respond. There's no need for anger or insults.

Bluezone
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HoleInTheSnow
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#9

Re: Microfaraday Capacitors: Fan Windings and Speeds

08/17/2008 11:37 AM

What is happenning on this forum of late ? There seems to be alot of anger/tension floating about. I was looking a one post, something to do with the olympics, and there was a considerable amount of abuse flying about (mainly from Guests I add).

I would hope that this forum would not tolerate this sort of behaviour and I plead with all users to refrain from such behaviour. While humourous reponses are fun to read and lighten the moment, abusive/rude responses are not.

Sorry if there are any spelling errors but hopefully you will understand what I am trying to say.

Kind Regards

Mr. WA Snow
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PWSlack
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#11

Re: Microfaraday Capacitors: Fan Windings and Speeds

08/18/2008 4:02 AM

Either it will be slower in coming up to speed, or it won't start at all. If it doesn't start, then the circuit protective device may operate, depending on its setting.

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Users who posted comments:

bluezone (1); electrone (1); gadgetman (1); HoleInTheSnow (2); howrang bajaj (2); Mark684 (1); PWSlack (1); Sparkstation (3); YWROADRUNNER (1)

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