samguan

My friend made one for me... All the tutorials on the internet say that you have to open it and do some wiring inside the power supply. But my friend just did some wiring with the existing wires that comes out of the power supply. We tried it yesterday and it was working fine.. However, when we set to charge at 3A.. the power supply sounded like it was struggling to provide the power and make a different noise..but it would still charge fine..I'm just scared that it might explode or something.

If I know where I can buy this in Toronto, I would rather spend the money on buying on..instead of making one..

Any ideas/suggestions on this?

Update: everything is working fine now... it's normal power supply sound. Because If I turn it on without charging, it's only the fan making the noise and when the charger starts, it's actually getting the power from the power supply. So it will sound a little different.

HJJFFFAA

Do you have a good power supply?

samguan

I was wondering why my frd him didn't have to modify the inside of the power supply.. the power supply was pretty old... 5 years old

sheograth

If you don't know what you're doing or how a switching power supply works you're better off just buying one instead of trying to convert a PC one.

samguan

I'm trying to find one right now...no idea where I can buy them...

sheograth

You've made tons of threads about this, and in each one people have told you where to go. A 12V hobby power supply is really easy to find - go to an electronics store and ask. Or just order one online.

dacaur

you need a 10 watt 10 ohm resistor or two on the 5 volt line, that's the red one. just connect it between any red and black wires...

The reason you need to open the case is to make it look nice and note have a spaghetti of wires everywhere. when you open it up you can cut the wires short and just have a connector going through the case and keep the resistors inside the case.... you dont NEED to open it, but it looks better and has less chance of shorting out if you do.

as for why it sounds like its struggling.. some power supply's have multi-speed fans that go slower when there is no load on the PS, and speed up under load when it needs more cooling.

samguan

he didn't use any ohm resister.. all he used was a on/off switched and connect some wires

DaveG55

Doesn't sound like he knows what he's doing then. There are many posts/how-too's on here about converting a PC ps for rc use. Just do a search.

Still, you'll be better off to buy a ps that's been designed for the purpose of powering chargers, etc. They can be found at any hobby shop or electronics shop - Do you ave Radio Shack up there? I know they sell them as does Tower and they can be found on e-bay also. Just look around, you will find them. Also, try not to cheap out too much on a ps. Like a charger, that's one thing it's worth getting a good one.

Sugafree

Lots of Cheap......yet Good Power Supply's to pick from.......

http://www.etronics.com/showcategory...entoryFilter=1

dacaur

Well, if the one you have works ok, there is no need to go out and spend a bunch of money on a hobby power supply. I used to use a converted pc power supply with no problem, until I found a nice 8 amp hobby unit at a secondhand store for $5.00....

Can you describe what you mean by this:

Do you just mean the fan went faster? if that's it then its just a load/temp sensitive fan, and you are fine, if you mean it made some sort of buzzing sound, that's probably not good... If it works then you should be OK without a resistor, but if your voltage is a low, a resistor would help bring it up... test it under load while the charger is charging...

samguan

I'm testing it right now and it actually works...and I checked the voltage with a multimeter and it read 12.X volt which is fine for my charger..

One thing.. my charger will charge for couple minutes and drop the A to 0.0A for 5 seconds and start charging again.. this cycle continues on...Is that a safety feature??

The sound is like the sound from the power supply when you first turn on your computer..i think it should be normal because my friend has been using it for 1 year now and he knows what he is doing..

The problem is that the cheapest power supply at my hobby shop a 4A, it's $60.. 6A, it's $99..

Evader ---> MGT

I made two of these as well, both with "230w" output for the 12v line which is total bullcrap because even with a just 50w pull at 2.4amps, the power supplies could not handle it and the voltage dropped well under 11volts, the minimum voltage for most chargers to work on. This cause my chargers transformers to get pretty dang hot!!!!

You're honestly better off buying a real power supply. Even by modifying many computer powersupplies with different resistors and stuff, you might only get 11v at 50watts, well under par for most chargers.

samguan

Actually, I have tested for a day now and it seems to work fine... charger is cool.. I checked the voltage comming out of the power supply, it's always above 12V.

hands without shadows

Modern power supplies need a resistor to be converted because they only turn on when there is a load. The display of modern chargers isnt enough of a load. Once the charger is charging the resistor does nothing but waste energy. If you can run your charger without the resistor then you dont need to add one.

Evader ---> MGT

Huh, I guess my two powersupplies just sucked... lol

rageworks

Here is a link on the ECU conversion. http://reckerclub.tripod.com/id105.html

rageworks

Here's another link. http://www.instructables.com/id/Conv...gular-DC-Powe/

rageworks

One more. http://web2.murraystate.edu/andy.bat...OWERSUPPLY.HTM

rageworks

Last but not least. http://web2.murraystate.edu/andy.bat...OWERSUPPLY.HTM
Sorry, double post.

hands without shadows

I'm kind of biased, but I like this one: http://www.rcuniverse.com/forum/m_5680951/tm.htm

rageworks

This is a pretty good deal on a power supply. http://www.hobbypeople.net/gallery/158301.asp

Sugafree

http://www.hobbypeople.net/gallery/158301.asp