downunder23

hi i have seen a few post's with this topic of using pc power supplies for rc supplies by converting them, i think they use a 120 volt input though. doe's any one know how to convert a 240 volt's input ac into 12 volt dc effectively
with out frying the unit it self or the unit's it's supplying power too (battery charger etc)
i have a power supply but am a bit concerned on specific's and am waiting untill i have all the information needed to keep on the safe side.
doe's any 1 know what safety measure's (like add a resistor or capacitor)
that will protect against over loading and frying the charger.

because i live in Australia we run 240 volt main's so i am playing with double the voltage than the 120 volts that the supply conversion is based on in the rookie zone section of rc-tech.(under pc power supply).

does any one know alot about electronics and what steps to take that will ensure a safe power supply using a 240 volt main's as input.
convert it to dc 12 volt out put and specific's on the wattage amp's difference's of the pc supplie's.
for example the supply i have has an
input and current of = 90-120 vac 4.0A
180-240 vac 2.0A ( switch selectable)

frequency =50-60hz

outputvoltage = +5v 16.0A
+12v 5.5A
-5V 0.3A
-12V 0.3A

THAT'S WHAT IS WRITTEN ON TOP OF THE SUPPLY ON THE STICKER.
so look's like the +12 volts is a max of 5.5 output but the funny thing is the 5v is 16.0A
WHATS THE MAX OUT PUT I CAN GET OUT OF THIS.

downunder23

[ADD ON TO PREVIOUS POST]

the max out put will be 12 volts obviously but the max output in amp's is the thing i need to know too, im not sure how the +12v, which has max amps of 5.5 and the -12v which only has .3 amps i need both of them to get usage out of it positive and negative so do i add them together? to get the correct usable 12v amperage rate?
or can i change the wiring inside of it to make the 12v output the same as amperage as the +5v which is 16 amp's (i want 12v 16 amp's output)
instead of a limited usaged 5.5 amp's

does anyone understand this?.........so much for short and sweet.........this is complicated. only experienced electronic people answer this.

krisnata

hello there

I live in Indonesia and also used 220V.

I try the PC power supply before and is tru you can only get about 5 amp with 12v. it is not enough for charger or tyre truer etc.

My recomendation is to get cheap notebook/ laptop power supply which output average 12 volt and has about 15 amp. those are better and cheap too.

if you need more power just, get two and pararel connect them. then you get 12V and 30 amps.

here laptop power supply cost about $10

meegosh

Laptop PS would be the best way to go I would imagine. It is probably the safer route to go also. Be careful when you are working on PC power supplies, some of those 480watt PSs can really give you a shock if you touch one of the capacitors in there. Trust me, seeing that I work at a PC repair business I get the pleasure of zapping myself almost on a weekly basis.

downunder23

yehe i have had the pleasure also of being zapped by the internal's of a pc woohoo im alive.....i forgot to turn the power off whiles muking around in there and it zapped me didnt feel like what id expect it would though felt like a really bad case of pin's and needles feeling in my finger's and hand i enjoyed it, lol, j/k.
yeah im a bit wary of doing it but ive already got all the part's so im a goahead with it......electricuted or not..

one question you may be able to prevent an electricution is when it is all complete (the pc conversion) for the dc output power what can happen as far as electric build up can the unit build up electricity and load up as it's used causing high voltage etc and cause an shock eventually and what measures can be taken to rule this out from happening?

krisnata

get 12v switching power supply from electronic store, they are waaaayyy cheaper than one intended for RC. they work the same ...

nwilcox88

iTrader: (5)

As a Systems Technician I could not resist about a year ago to try this. Was not worth it all. The voltage was not consistant enough to power my Integy Dyno like it needed to be.

jbrow1

iTrader: (28)

I built a couple also. As said above it wasn't worth it. They would work, but better on 4 cell batts than 6 cell. If you spend the money on a high output computer power supply it can be done. But unless you have it sitting in your basement already not worth it as it's kind of a pain to do, and you can buy a decent rc power supply for the same or less than a good computer one. The older computer ones with an actual on/off switch are much, much easier to make one out of if anybody goes ahead and does it. If you don't have at least a 250 watt one don't bother. And put a good sized LED or brake lightbulb on the 3 volt leg to make more consistent power on the other legs.

semore

iTrader: (6)

I amm also a systems tech and had to try it also. I had the same results as the others had. The only way to get the 12 volts side up to 12 volts is solder so resistors and it was still not a consistant 12 volts. Its really not worth it. I bought a PS from radiooo shack 15amp for liike 70 bux.

krisnata

he he,..... Radio Shack Rule........