Power Supply Talk
 

Hi there. I've now come to the point in electric racing that I need a bigger power supply. Charging two 7.4v 4100mAh at 2c. I set the charger for 8amps. Doing this the last three weekends finally toasted my little 10amp power supply.

I was cruising ebay looking for an ATX power when I came across this little unit from Wondermotor. http://www.wondermotor.com/powersupply.html Anyone know of them? They are selling for $75 on ebay and they are 13.8V at 26A. The biggest draw to this PS is the footprint, and I assume light weight.

I'm in search of a power supply that doesn't take up much room. Lots of traveling to the RC races and the large PS just isn't to my liking. And since my PS took a dump today I'm needing something fairly quick.

I just started researching the ATX PS units today. So far it doesn't look to bad to get one set up for my needs. I have no concerns as far as soldering and fabbing up a computer power supply. The work looks to be well within my mechanical skills.

I'm going to the Computer Fix-it shop tomorrow morning to ask them some questions. So I might end up getting it set up at the race track tomorrow.

thanx for any thoughts or suggestions
chris

No experience with those. Have you looked at a Pyramid 30amp supply - they are less than those and have a good rep.


http://store.buyreliant.com/servlet/...itching/Detail

Thanx. Ya know, I've looked at them before but I guess I missed the physical dimensions. Didn't realize the Pyramids were as small as they are. that'll probably be the route I go with.

I've been using 25a Rad Shack PS and next time I need another, I'll be getting one myself.

I have this power supply.It has been running up to 4 chargers and tire truer,dyno etc for 4 years now.Never skipped a beat:)

+1 for the Pyramid sypply.
I have been using Pyramid power supplies for over 25+ years and this unit is the best do far.
I made a small junction box with Banana jacks that I attached to the top that I can plug four items into.
You will not go wrong with this pawer supply.
Bob Oaks:D

i think if you want to go budget (i do everytime) the best thing to do is open an old pc. if you can find a way to hav the power supply turned on (some need connecting an "on" lead to an earth) then all u need to do is use the yellow (usually) for 12v dc. otherwise you could try a car battery charger, depending on what amps they are rated for. i think ours is only rated for 6, but its a lame crappy one

I've read a lot of warnings from charger companies not to run their chargers with a auto type batt chargers. Look in the manual for ICE charger, warning is listed on page 3 - "Do not use automotive type charges to power the charger".

The power they supply is not 'clean' enough and can damage the charger. Get a proper power supply - you can find inexpensive ones from places like HobbyCity for cheap.

i've used the ice for over a year with the pyramid 30 amp no problems at all.

+1 for pyramid

the 20 amp is good also. for 50-60$ you cant beat it

+3 on the Pyramid.. I got mine on Amazon.com, it works well.

GOOD thread on using a PC power supply in a sticky on the electronics section at rccrawler.com forums, well worth the reading for those interested... (sry no link, apparently i don't have enough posts to do that yet). Lots of pics, descriptions, instructions, etc. I'd imagine a pc power supply should be clean enough to run a charger, after all, they are designed to run $$$ computers with very tight tolerances for voltage.

I'd rather just buy one rather than convert, but I have converted a few then gave them away or some them.

http://www.instructables.com/id/ATX-...ly-Conversion/

http://www.wikihow.com/Convert-a-Com...b-Power-Supply

http://letsmakerobots.com/node/1355

http://4bangerjp.com/forums/index.php?topic=259.0;wap2

Takes 10 posts.......

I have a handful of Power supplies...
The old Pyrmaid 30amp boat anchor used to be my choice, but now I do convert old PC supplies.

I put an in-line fuse holder & 15amp automotive fuse, & some female banana jacks on an old Dell 400+ watt. I have had no problem pulling 10 amps to break in mod motors on the ICE charger & the supply is reasonably sized.

Newegg has a hand full of "Single 12+ Rail" supplies for a reasonable price
You can definitely go bigger & "Dual Rail", but I don't know if there are any problems crossing rails.

Here are a few based on ratings...
Junker name brand:
$30 - 15amp
http://www.newegg.com/Product/Produc...82E16817182006

$25 - 20amp
http://www.newegg.com/Product/Produc...82E16817255040

$55 - 35amp
http://www.newegg.com/Product/Produc...82E16817182010

Good name brand:
$40 (but has rebate) - 18amp
http://www.newegg.com/Product/Produc...82E16817153023

$60 - 35amp
http://www.newegg.com/Product/Produc...82E16817148008


And the one I want... (ooohh! now on rebate)
$60 - 34amp
http://www.newegg.com/Product/Produc...82E16817148005

Find the green wire in the 20/24 pin header, cut that & a black & tie them together...

http://i15.photobucket.com/albums/a3...CSupply001.jpg

Cut all of the Blacks & Yellows in all of the misc connectors off & tie all the Yellows together as one, & all of the Blacks as one. put an in-line fuse holder on the Yellows & pick a fuse just below the rating of the supply.

http://i15.photobucket.com/albums/a3...CSupply007.jpg

And if you have time make a pretty tap box for hooking up more than a couple chargers.

http://i15.photobucket.com/albums/a3...CSupply004.jpg

I also didn't bother opening up the case to mod any connections, I just chopped the ends off the existing wires.
I also don't have any load resistor on mine, the charger in the on state seems to work fine as a load so far.