stopped repairing ATX power supply many years ago, thanks to the new cost is very cheap. It is not worth to repair because the parts are sometimes more expensive than getting a new power supply. Search ATX power supply spare parts was not easy, as many of them can not even find them online. Not only that, a number of complex and different planned power supply manufacturer has absorbed our precious troubleshooting time, because we need time to understand how all these different power supply designed to work.
Some power supply designs were the PWM IC (UC3842) and power FET, some use the double transistors while some only one primary side of the power IC. As a manufacturer wants to be taken in the design of compact size, number of secondary or even primary power supply circuit was built in a modular table (small plate). This made troubleshooting more difficult, because many times the probe can not reach that point in the investigation.
The real reason I stopped repairing ATX power supply was the profit. If you spend the big buyers prefer to buy a new unit warranty for one year. If you fill too low, you can end up on the losing side because instead of parts, electricity, etc., charge a fee earned reasonable profit margin does not extend the time spent on troubleshooting it. I am here not to discourage you to stop repairing ATX power supply, but if you have the time to contact more cheap power supply components, easy access to many power supply and wiring diagrams, etc., you can go ahead to improve it.
right back to the article, one of our clients asked me to repair the ATX power supply. I told him to get a new one (because it was very cheap), but said he could not find one that fits the customer's CPU. He wanted the power to either the same size or smaller than the original one of equal or greater performance, but all I could find a standard size power supply!
The benefit to my clients, it's not my best to help him to repair the ATX power supply. If the power supply was switched on measurements. The results surges. The 12-volt line shot up to + 13 V and 5 V line was 5.6 volts. After removing the cover, I found it very dirty and my vacuum cleaner and brush to clean off the dirt. Then I saw four filter electrolytic capacitors also bulged the cover page.
As you know, our electronic repair shops not only see things only from one side; It is that the other party. What I mean was, try to see if there are any suspicious items that contributed to the failure of the power supply, such as broken parts, dry joints, loose connection, decay glue and etc before you start checking the suspected area.
What I saw there were on the primary side components covered with decayed glue in the picture. It is necessary to carefully remove the rotten scrapping the layers of adhesive while maintaining the outer layer of the components. Once you have finished, we clean the diluent. Corrupt adhesive may cause severe or intermittent fault electronic equipment because it may lead.
If repairs ATX power supply, make sure to check the fan because the heat caused some power failures caused by faulty fan. The purpose of the fan to suck all the heat generated by the power supply inside the machine. In order to allow smooth running of the fan, the service has a Philips oil based spray as shown.
After the exchange of four electrolytic capacitors and removal of decayed glue, then plug it into my eyes, this is a motherboard testing hard drive performance with the ATX power supply, and measure all of the output voltage. It seems as if the output voltages were back to normal. If everything is okay, you can try a working CPU to check the display.
To test your junk motherboard first, so as not to cause my good motherboard go bad just in case, if the output voltage is still very high. Better safe than regret later. By the way, you can not control the power supply without load already is on for a while, then it stopped. If it is not junk motherboard you can always at least connect the hard drive and a jumper cable connector, turn on the ATX power supply.
Do you know that most of ATX power supply uses a dual Schottky rectifier to convert the C wave of DC voltage? Even the LCD monitor power supply, dual Schottky rectification is used. For your information, check diode Schottky diode is different from normal controls. Analog meter set to X10 K ohm, you have to show some leakage reading, if the opposite bias test. If this element is very easy to fail to have a replacement, of course, is that one of the right specification. That's all for today, I hope you enjoy the article and come back often to check out the latest repair techniques possible that I will share with you.