Just out of curiosity what do you guys use for high power DC power supplies? I just recently acquired a 74" Edge and it's my first electric plane of substantial size - in the past I've had nitro and gas. To me, the batteries are massive (6 cell 6000maH) and are capable of being charged at up to 5C (that's 30A of current!).

Now I have no desire to charge my batteries in 12 minutes as I have five of them and when I'm home I'm in no rush. At the field I may want to crank it to 2C-3C to get more flying done in a day but I don't need any more than that. Still, that's a total of 36A to charge two batteries simultaneously at 3C from the same power supply.

I was debating between buying a Motomaster Eliminator Powerbox because they were on sale at Canadian Tire and would be convenient for at home and at the field charging as well as boosting cars or a hobby grade power supply. Both of those options would have run me around $150-200.

Instead I figured there should be a way to mod an ATX power supply from a computer into a 12V power supply and that getting one to do 30A+ shouldn't be too difficult if I combined the 12V rails. Sure enough, I googled it and there were tons of tutorials.

So I went to Future Shop and bought an open box 500W power supply capable of 18A on the first 12V rail and 16A on the second 12V rail. Combined that's 34A. I ended up spending about a hundred bucks in total because I needed some tools that I didn't have lying around but the result was a reliable regulated power supply with 3,5, and 12V outputs capable of delivering more than enough current for my present needs. Of course if I need more eventually I'll just buy a bigger power supply and make another one I just wanted to keep costs down on the first one in case I screwed it up.

I've uploaded some photos but if anybody ever is in need of a power supply this is the way to go! I got this supply new for $20 and it works great! All you need to go with it is some binding posts, heat shrink tubing, something to put a load on the supply so it will turn on (I used a 12V 10W light bulb) and some time.

I'm going to build a case for it and add posts for the 3 and 5 volt outputs as well as a USB output in the next week or so so please don't criticize the binding posts hanging out of it with the small bits of metal exposed at the back. I know it can't stay like this. The initial goal was to get it functional.

http://stephensampson.ca/public/pictures/psu/1.jpg

http://stephensampson.ca/public/pictures/psu/2.jpg

when my wife was working, her department turfed 5 or 6 old computers. i took the power supplies...

I did the same thing you did, but kept it at the 12V from 1 rail. I have no need for more output..

Hi Stephen. I use one of these and it's a workhorse. Doesn't even get warm. Here's a link to the power supply. I didn't get mine from them though. Jeff at Mighty Small Cars used to carry them. He may still have some.....MIke


http://www.waterproofleddriver.com/sale-291962-350w-30a-ip20-12-volt-led-power-supply-epa3050b-over-current.html

---

Here's a link to one on ebay.


http://www.ebay.ca/itm/360-WATTS-DC-POWER-SUPPLY-OUTPUT-12-VOLT-30-AMPS-METALIC-WITH-COOLING-FAN-INSIDE-/111414176071?pt=LH_DefaultDomain_2&hash=item19f0cd6947

Looks like I made the right choice not to buy one intended for the hobby for the $150-$200 they cost. That one for $30 plus shipping would have been a much cheaper option had I known but at least it was a fun project (though only a couple of hours) to make one.

Always more fun to say you made it yourself! :)

You can also replace the lamp with a high power resistor, and that'll only cost $3 or $4.

Dan

Danster wrote on Nov 9^th, 2014 at 10:48am:

You can also replace the lamp with a high power resistor, and that'll only cost $3 or $4. Dan

That's what I did Dan -  bought a 1 ohm 25 watt resistor at what was then Radio Shack...actually think i had to buy 2 because they  were packaged in a bubble pack on a card....... 8-)

It's riveted to the case, so gotta be careful - you can burn your hand a bit after the thing runs for a while...

I wanted to use the light because otherwise the supply has no indication that it's powered on. It's now mounted on the inside of the case neatly and actually looks alright. I was going to mount LEDs to the case as an indicator and use a resistor for the load but this was just easier.