Tommygunn792

Fair enough but it seemed like a hell of a wallop for 5 or 12Volts, presumably it's the current that gives it the kick?
Concerning having a load to the PSU, I don't turn it on unless the charger is plugged in or some other item I'm powering.

Tom.

Zrock

the belt you felt might not be teh 12 or 5v it may be the incoming 112v on that side its hard to say.. Putting a load on the 5v side increases and steady's the voltage on the PS

Tommygunn792

Zrock,
As long as it is all normal then fine. Mind you the click/tick noise is a small concern but at the moment I'm putting that down to components energising.

I got belted with 230V, I'm in Italy!

Tom.

karolh

Tom, I sent you a PM.

Zrock

ouch... the clicking your hearing could be some sort of built in voltage converter? Im not to familiar with electricity over their

ProStreetCamaro

Hey gentleman what do you think of this psu? 500watts and 40a on the single 12V rail. I am looking for a good solid powerful psu to power a 400watt Turnigy. I want to charge 2 X 2s 500mah and sometimes 2 X 3S 6000mah packs. charger http://hobbyking.com/hobbyking/store...arehouse_.html

psu http://www.microcenter.com/product/4...us_Power_Suply

WhuteverMichael

howdy Im way new here how exactly do I save this thread to my pf? plz and ty

crapshooter

guys, i just bought a new pcu / atx power supply to convert into a power supply for my lipo charger. my issue is it will only turn on for about 2 secounds before turning off. i have done the proper conversion of using 4 yellow wires / 4 black wires for 12 volts and done the green wire to black wire join i have also installed a 10 ohm - 10 watt sandbar resistor on a black wire to red wire [ 5 volts ] i have tried to get this working but it won,t let me. any tips ? its a 550 watt atx. HELP.

dmccormick001

Most ATX PSUs have a small gauge brown wire that is a "sense" wire, it must be connected to the 3.3 volt (orange) rail. Look at the 24-pin connector that goes to the motherboard, you'll see that it is wired together with one of the orange wires. If you have removed that connector, you may have to solder the brown wire to the spot on the PCB where the orange wires are/were.

Also, some chargers have large capacitors in them that charge up when the charger is turned on, so you have to turn the charger on BEFORE you power up the PSU, or it will trigger the over-current sensors in the PSU and it will shut down.

Seased

You are always a great help to everyone here! Thank you for this.

king bily

I suppose the assumption was that you would read the section on remote sensing carefully -- it does reference sensing on the +5v and +12v rail. I have also seen one supply with a sense wire on ground.

I've converted around 80 or so supplies and run latch and voltage level tests on well over 200. There is a lot of variation across models - some supplies will latch and hold without a preload; some will not. A few will run without reconnecting the sense wires; the majority will not. Stability under load varies considerably -- Antec and Sparkle have performed well. To cover all the bases in the conversion process places some burden on the reader to be equally diligent.

If there is mis-information in the conversion, I would appreciate knowing.

init4fun

Excuse me "King Bily" , BUT , , is there ANY reason why your post is an exact cut and paste of Andrew's post from 2007 ???? Maybe the fact that your a BOT has something to do with it ????

Consider your Bot butt reported , and hopefully banned real soon ......

Andrew

How very interesting. I haven't visited RCU much in recent years, but decided to view some of my favorite forums over the last couple of weeks. Imagine my surprise when one of the last posts in this thread was one of my own, albeit plagiarized. But, even more astounding is the fact that init4fun made a connection with a comment that was 12 years old!!!

andrew

Enrgtech

Please note that the high voltage wires that come in from the socket in the side of the PSU should be avoided at all costs! Don't cut them, join them or touch them.
The only wires you need should be bundled together and sent outside of the case.
Identify these wires and ONLY use them, don't grab any other wire that resides inside the case.

Please note that 'brown' is not a very common color on power supplies.. it is on some.. but unless you make sure you know what the wire is, don't tie it to anything.
Do you still have the connector for the power supply? The part that mates to the motherboard?
You can verify the colors by looking at a pinout for that connector. Colors are not a reliable method.

The wires you should need are as follows, and will be part of the wire bundle that exits the PSU and goes to the largest connector.
Yellow - 12V (Ignore the Yellow/Black stripe for now)
Black - Ground (0V)
Green* - Commonly green, not always! Labelled as 'PS-ON' when you google an "ATX pinout"
Please grab a meter and test these wires before using them. They are common colors... but you must always be certain.

RachelGomez161999

There are several different coloured wires attached to the 20-pin ATX connector providing several different voltage outputs such as +3.3V, +5V, +12V, -12V, -5V as well as a number of black ground wires and a couple signal wires as shown in the following image along with their colour-code and description.

The newer type ATX12V PSU’s are a little more tricky to convert as they use a ‘soft’ power switch function and require a much larger external load resistance. To get them to start-up, or switch-ON, the supply must be loaded to at least 20W or 10% of the rated power for the larger 600W+ PSU’s. Anything below this the power supply may run, but regulation will be very poor less than 50%.

Also some of the newer and larger wattage PSU’s require pin 14 – Green (Power-ON) to be connected permantly to ground using a SPST switch. Obviously each type of PSU is different from different manufacturers, so you need to find what works for you.

Again the voltages that can be output by this unit are the same as before 24v (+12, -12), 17v (+5, -12), 12v (+12, 0), 10v (+5, -5), 7v (+12, +5), 5v (+5, 0). Note that some ATX12V power supplies with a 24-pin motherboard connector may not have the -5V (pin 20) white lead. In this case use the older ATX power supplies with a 20-pin connector above if you need the additional -5V supply.

Any old PC power supply unit makes an excellent and cheap bench top power supply for the electronics constructor and the process to convert ATX PSU to a portable power supply is relatively straight forward. The power supply unit uses switching regulators to maintain a constant supply with good regulation and short circuit protection cause the unit to shutdown and be re-powered immediately if something goes wrong.

The only downside to convert ATX PSU to a bench power supply is that the cooling fan’s rpm responds to the amount of current being drawn from the PSU so can get a little noisy. Also the ATX PSU requires a certain amount of fresh air to keep it cool inside which may not be possible when laid onto a bench.

All in all, converting an ATX PSU to a bench power supply is an easy project with many uses. Not bad for something that would otherwise get thrown away but remember, unplug from the mains supply first before you start any modifications as you are the only person responsible for your own safety!

Regards,
Rachel Gomez

walishahid333

my is atx psu i will check this

Claraa12

Converting an ATX power supply for use in RC (remote control) applications can be done with some modifications.

Claraa12

However, it is important to note that this modification can be dangerous and should only be attempted by individuals with experience and knowledge in electronics.

Claraa12

Here are the basic steps to convert an ATX power supply for RC use:

Claraa12

Identify the wires: The first step is to identify the wires that you will need to connect to your RC equipment. The ATX power supply typically has four wires of interest, which are the +5V, +12V, -12V, and ground wires. You will need to identify these wires and determine which ones you need for your RC equipment.

Claraa12

• Disconnect the unused wires: Once you have identified the wires you need, you should disconnect the unused wires from the power supply to avoid any accidental short circuits.
  
• Short the green wire: Locate the green wire in the ATX connector, and short it to any black ground wire using a wire or paperclip. This will turn on the power supply.
  

Andrew

There is a lot of variation across models - some supplies will latch and hold without a preload; some will not. Later ATX versions will generally hold while the earlier production models will require a preload on the 5V rail -- if your PS does not power up when shorting PS_ON (green) to ground, then a load resistor may be needed.

Design Guide updates of importance to individuals converting their power supplies. The +3.3 VDC remote sensing wire (brown) is connected directly to the orange +3.3 VDC at pin 11 of the power connector (pin 13 if a 2x12). The sense wire will usually be of a lighter gauge (22 AWG) than the power wires (16 or 18 AWG) and its purpose is to monitor the voltage at the connector in order to provide feedback for voltage compensation by the supply.

If your PS has two wires attached to the same pin on the motherboard power connector, orange +3.3 VDC and a brown sense wire on Pin 11 for example, then these two wires should be joined when you make your conversion. Some power supplies may also have sense wires running to the +5 VDC and +12 VDC connector pins. If there are multiple sense wires, then they will usually be of the same color as the primary supply wire, but of a lighter wire gauge. These sense wires will also terminate in a different location on the PS printed circuit board than the heavier supply lines. As with the +3.3 sense wire, these additional wires should also be connected to the corresponding supply lines. Failure to complete these connections may result in your power supply not latching into a Power_On mode when switched on.

A cautionary note: Most supplies will have at least two smoothing capacitors located downstream of the rectifier -- these are relatively hefty caps and may give a good jolt if touched immediately after unplugging the PSU. Prudence would dictate either grounding these or initiating power_on without AC before mucking around much with the board.