my real question is, can i merge the 2 12v rails? would it even be possible to get 2 power supplies the same and do it like that (connect them in parrallel?)

If you try to merge the rails, be careful. I had a dual 12v supply and heatsink got quite hot quickly. Each rail would have to have EXACTLY the same voltage and even then I dunno.

Some PS units have a trimmer pot located somewhere on the PCB. You can use this to tweak up the voltage a little. I have one I was able to get to ~13v unloaded. Not only does this help keep the voltage above 12v when loaded a little, but the higher voltage requires less current at the same time. Be careful though, if you do see a pot, make SMALL changes while watching the voltage. If it doesn't change, put that pot back to the original position because it's being used for something else.

If the trimmer pot is not there, you can sometimes force a little better regulation by adding (or increasing) the preload on the 5v and/or 3.3v rail.

It sucks that all PSUs are not built the same because what works for one doesn't work for the other...

well i was brutal before putting it together (its still sitting on my table 1/2 finished) and ran it hard with both rails loaded as much as my 4 chargers could... it got warm after 5 mintues but i wouldnt call it hot. just warm to touch (dont have a temp thingy)

ill have a look for that pot... this could help heaps. are there any downsides to turning this up or is it just there so they can accureately tune it at the factory to make sure even though the components may differ in quality it still outputs correct voltage?

anyone with electrical knowledge please help!!

As far as I know, it's just there to tweak the rails to be more in line with PC voltage specs. Turning it up a volt or so should cause any issues as long as it doesn't go up higher than that. Generally, I'd shoot for no more than 13.5v just to be safe. Of course, the 5 and 3.3v rails will go up as well, but you're not using it for a PC anymore...

Also BE CAREFUL when you stick something in there to adjust the pot while the PS is running. There are dangerous DC voltage levels in there and can cause severe shock!!

If at all possible, use a well insulated screwdriver to adjust it. Better yet, use a TV tuning screwdriver (all plastic) if you can find one.

here are some pics of the underside of the board. there are no pots that i can see, are there different types which look completely different to those commonly seen? thanks

see how closely the 2 rails are divided, do you think that there would be any way without blowing it up to try it?
o yeah i forgot... the 2 smaller blobs near the side, in the middle of photo 1 are the 12v rails... the other HUGE blob is the common rail. hope that makes sense!

yeah i was planning to turn it off use an insulated screw driver (wait till the voltage hasdrained from the caps of course) then adjust it a 1/16 of a turn or something then turn it on and re measure. im not keen on touching it while its connected to 240v!!
btw, where would the pots be??

my power supply
 

well i decided to try my luck again on fleabay i ended up with a radio shack 25 amp 13.6v power supply anyone have any feeback on my purchase from personal experience knowing that it is from radio shack.
oh to keep it in perspective it was 70 bucks shipped and it looks brand new

this is going to be enough power for my hyperion 0610i charger correct?
there is no other spec i should have looked at just amps and volts, yes
thanks

Well I would have just got a good pc powersupply from Newegg for $40 shipped and performed Brian's mod.

It was very easy and I'm very happy with the results.

http://www.newegg.com/Product/Produc...82E16817341012

its my understanding that's not enough amperage for a Hyperion 0610i i had looked that though i also wanted a clean appearance

I use this with mine:
http://www.hobbypeople.net/gallery/158303.asp

no issues on power delivery, dual output and it looks decent.

my club doesnt allow hackjobs (found out after making it look great) so i went and got the $39 from hobby city... paid on wednesday, and its in the country as we speak... pretty darn good service and FAST shipping for a low price....

its only a 16A but at 14v which is better than on 12v like my modded one.... and if it blows up, they assure me, if it wasnt overloaded (got a wattmeter to find out) i get a free replacement :)

sounds like decent insurance, and its 1/2 the price of a similar unit to dickyT's with only 12A. blew 3 of these (all replaced for free) running an 8A charger off it.... must have been quite inefficient!!

anyhow, ill only be charging 4s a123 @ 10A max, so this will be enough for that. (or the i charger 106B which is more efficient, cheaper and better for customer service!(and highly accurate balancing as each one is supposedly tuned from the factory)




O AND BTW: DONT CONNECT 2 RAILS ON THE PSU LIKE I DID, THEN TOUCH THE HEATSINK (usually does nothing, and is grounded)... you end up with a freaking big fright and a HUGE SHOCK... i refuse to touch that one again LOL...24V @ 42A... lol.

maybe i'm confused here? Mine is 20 amp not 12.

Well, you can try paralleling the two rails and watch temps. It might run fine, it might not. Also, if possible, get a voltage reading under load when seperate and then again while paralleled. It should dip less when paralleled. If not, then you aren't gaining anything.

The pots (if present) could be anywhere on the component side. They are typically small and may have a bit of goop on them to prevent them from "drifting".

@e-rev project: 25A @ 13.8v is 345w. Accounting for charger efficiency, that leaves you with around 276w for the batteries. If you can tweak up the voltage a tad to something like 14.5v, it would take less current.

well, the only reason i wanted to parallel, is to have only 1 output. i zipped myself before i had any time to do testing... ive given up, it really really hurt.

BUT. can i connect 2 seperate powersupplies (the ones from hobby city) in parallel or will that cause issues too?
thanks,
ryan (if i could do that, it would be more than enough current needed, for $80)

IIRC that supply is made by Samlex for RS and has an excellent rep as a PS for rc use. The way Hyp specs PS for the 0606i is 350watts at 15v. Specs you quoted is equiv 340watts. Gotta believe you'll be able to do 95% of everything you want to with that one. Thats the one I wanted when I was looking for mine, but took a new 20a PS by ProPeak in a trade and so far, its been all I've needed.

considering all you need power wise from your charger to charge a 5000 6s lipo is 111 watts you should be fine, you could add 21 more watts for efficiency