Build a 24v 15amp power supply.

Does anyone know how to build a power supply that will provide 15 amps at 24vdc. I need one for the plasma speaker and it pulls 10 amps at 24vdc. I am hoping to keep down on costs as a similar pre-built power supply would be in the hundreds of dollars.

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mchiper6 years ago
Most AXT power supplies provide +12V dc (15 amps) - 12V dc (0.6 amps)
Connect between +/- 12v will get you 24v dc (0.6 amps)
Use two power supplies!!
Connect outputs in series and get 2x the voltage at rated current.
Connect in parallel and get 2x the current at rated voltage.

BUT most of these power supplies connect the output GND (black) to
chassis ground. This prevents being able to connect outputs in series.
So.. Open the cases and break that connection.
On mine it was done with a small pad under one of the circuit board mounting screws. All I had to do was scrape it off.
Could you please elaborate on breaking the GND to case connection? I looked at mine and the ground wires have traces that go to other components as well as the corner screw... Can I just insulate that corner from the screw?
mchiper mchiper6 years ago
You really meant to say "Most ATX power supplies", didn't you?
Yup !!
dafonso6 years ago
Last time I built a power supply of that magnitude bad things happened. It turns out just about every component I used was flammable. Redesign's answer is the most foolproof. Building a large switching supply can be (literally) painful.

That said, you could go some place like http://www.trcelectronics.com/24-volt-power-supplies-high-chassis-1.shtml and grab yourself one for around $100. 24V is common in machine cabinets so there are plenty of parts out there for it.
jeff-o7 years ago
Heh, I just donated exactly what you need to my local hackerspace.  Sorry, I suppose that doesn't help much.
I am Bob (author)  jeff-o7 years ago
What is a "hackerspace"? I haven't heard of this before.
jeff-o I am Bob7 years ago
It's a common area, usually a large rented space, where members can come together to share tools and equipment that would normally be too expensive for individuals (such as a laser cutter) or that they couldn't keep at home (say, if they lived in an apartment).  It's also a fantastic place to socialize, or get help with your projects.  A monthly membership fee is paid by each member to pay for rent and utilities, and for equipment and supplies.
lemonie7 years ago
You either find a 24V truck-battery, or a pair of 12's or something with a big 24V-ou transformer. This isn't really a make, it's a "where do I get?"
If you've got it's pretty easy, but do you need 24V, or is that just what you're using?

Looking at UK sources, you could get one for less than 150 bucks US
Re-design7 years ago
Buy a 24 v. 20 amp transformer and bridge rectifier and filter caps.

Or series 2 12v. 20 amp transformers and the other stuff.

You'll find that the transformers that are that powerful are going to be expensive even if you can find surplus unless you get really luck.

 You could series two nice car batteries.