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Old 06-01-2003, 11:03 PM   #16
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could someone plz tell me how to convert it proply cause im have troubles. when i turn up the amps on the charger the supply turns itself off and u have to unplug it and plug it back in to get it going again

NEED HELP
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Old 06-01-2003, 11:18 PM   #17
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You need to install two 4700uf 65v capacitors, connected in parallel, from the +12v terminal to the common terminal. You can get these from Radio Shack. Make sure you get the polarity correct or the capacitors will very likely explode.

After rereading your post this may not be your problem. Sometimes a PS will shut off when you first try to power up the charger. The above solution should solve that problem. You may be exceeding the amp limit of your PS. Some PSs don't have much capacity on the 12v side. When selecting a PS for this application read the label on the PS and pick one with the highest +12v amperage rating that you can find. The ones I use typically have a 12A - 15A rating. A lot of the ones I've seen have an 8A rating. Not saying that it won't work, but personally I wouldn't use it for this application.

Last edited by calvin; 06-01-2003 at 11:59 PM.
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Old 07-22-2003, 10:53 PM   #18
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OK here's a question.

I've just finished converting my 2nd PSU. First went no problems but the output is a little low for the CDC.

The 2nd went no problems either putting out a nice 12.09v however...when running the multimeter around it to make sure all was safe I have found that the common/-ve rail and the external case are connected. i.e. I can put a multimeter on the +ve terminal and the external case and get 12.09v. I also get continuity from the -ve terminal and the case.

It seems to be doing this from the board itself i.e. you can see the circuits that connect to where the case screws together. and I can see/find any shorts anywhere from my work.

Just wondering if anyone else has found this?

This is NOT the case on my first PSU.

Help appreciated as my new CDC is lifeless at present!

Cheers

Andy
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Old 07-23-2003, 07:45 AM   #19
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did you put some sort of cover on theinside case??
thats what the instructions tell you to do

i would just tape the inside except for the vents
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Old 07-23-2003, 08:06 AM   #20
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I've done it twice with ATX power supplies. Both work great.

One is 4A the other is 12A. I did 4A because its tiny and I was using it for micro racing so I didn't need a big output.
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Old 07-23-2003, 05:52 PM   #21
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same here

except this other one kept on blowing a fuse

so switched to another

some crappy china comp supply
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Old 07-23-2003, 07:17 PM   #22
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Quote:
Originally posted by Calvin Ng
did you put some sort of cover on theinside case??
thats what the instructions tell you to do

i would just tape the inside except for the vents
Nope...but nothing is shorting....i think its happening on the PCB
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Old 07-23-2003, 07:35 PM   #23
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lol i dunno what your talking about

dont know the inside stuff
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Old 07-23-2003, 09:24 PM   #24
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I cant see how any of my mods could be shorting. I think the Printed Circuit Board actually connects the -ve rail to where the external case mounts to the board.

Hence I'm wondering if the -ve rail is supposed to be common with the case?

Aside from this it works a treat.

A
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Old 07-24-2003, 07:40 AM   #25
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but then he says to put a cover into it to protect anything from touching the case like a 2L pop bottle cut it so it rounds
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Old 07-24-2003, 04:33 PM   #26
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Quote:
Originally posted by wrxmy99
The 2nd went no problems either putting out a nice 12.09v however...when running the multimeter around it to make sure all was safe I have found that the common/-ve rail and the external case are connected. i.e. I can put a multimeter on the +ve terminal and the external case and get 12.09v. I also get continuity from the -ve terminal and the case.
Andy,

If you're using an ATX type power supply, look closely at the input. You'll notice that the earth from the plug is screwed to the case. Connecting the positive terminal on the output to the case will give you a complete circuit. I wouldn't worry too much about it.
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Old 07-24-2003, 05:19 PM   #27
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OK thanks..

Does this explain the continuity from the -ve terminal and the case?
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Old 07-24-2003, 05:31 PM   #28
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intresting i'll keep that in mind when working with comp supplies too

thanx
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Old 07-27-2003, 05:06 AM   #29
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could some one plz give me a step by step guide on how to set one up from scratch.

thanks
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Old 07-27-2003, 09:48 AM   #30
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http://www.magicookie.com/prodigy/psupply.htm

works perfect give it a shot
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