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How to make Regulated Power Supply

Manick9

Sep 14, 2011
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24*1.414 i think thats why. current i may have measured wrongly.voltage i am sure.
 

Manick9

Sep 14, 2011
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I used a 7824 regulator to get output to 24.1V output current is 11.15A.I want to reduce the current to 3A. I got 33V from the bridge rectifier and ard12A.Shd i put a resistor from the bridge rectifier/ from the output from regulator?must it be in series or parallel?what shd be the value of the resistor and power rating?
 
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(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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Jan 21, 2010
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There's no way you're getting 11.15A from a 7824.

You need to do absolutely nothing to reduce the current. Simply remove the short circuit from your power supply. (I am presuming you're putting the ammeter across the power supply rather than in series with it)
 

Manick9

Sep 14, 2011
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i measured it in parallel thats my mistake.i am forgetting my basics.where do i place my ammeter?
 

Manick9

Sep 14, 2011
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I get 0A when i measure in series.is it because there is no load which draws current?
 

(*steve*)

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That's right.

And it will be the load which determines the current (up to the max the 7824 can supply -- which will be well under 1A unless you have a reasonable;e sized heatsink on it.
 

Manick9

Sep 14, 2011
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I have big heatsink.i need 2Amp for the motor will i be able to get it or i wont?
 

davenn

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Sep 5, 2009
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I have big heatsink.i need 2Amp for the motor will i be able to get it or i wont?

not out of a 7824, its a max of 1A with a good heatsink

for greater than 1A you will either have to have a current pass transistor
or a higher current rated regulator say a LM 338 which has a peak of 5A

cheers
Dave
 

Manick9

Sep 14, 2011
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i will have to change the regulator then?will i be able to measure the current b4 the regulator?Is there any other ics that gives 24v output and ard 3Amps?
 
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Manick9

Sep 14, 2011
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I have got the output.Now i just have to test whether the motor works well
 
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