I’d stopped repairing ATX power supply a long time back because of the new one cost very cheap. It’s not worth to remedy it since the spare parts sometimes were much more expensive than obtaining a new power supply. Looking for ATX power supply spare parts wasn’t easy as most of them you can’t even find them on the internet. Not just that, many complicated and different created by power supply manufacturers had eaten up our precious troubleshooting time too because of we need time for you to know the way every one of these different designed power supply work.
A number of the power supply designs were using the PWM IC (UC3842) and power FET, some use the double transistors although some use merely a single power IC in the principal side. Because of the manufacturers wants the design to be made into compact size, many secondary or even primary power supply circuit were build in to a modular board (smaller board). This made troubleshooting even more difficult because often times the meter’s probe can’t reach to the testing point.
The true reason I’d stopped repairing ATX power supply was the profit margin. In the event that you charge to high the customers rather buy a new unit with twelve months warranty given. In the event FFPOWER hat you charge too low, you may result in the losing side because of the components replaced, electricity and etc. In the event that you charge reasonable, the profit margin gained can’t even cover your time used on troubleshooting it. I’m here to not discourage you to prevent repairing ATX power supply, however when you yourself have the full time, have contacts getting cheap power supply components, accessible many power supply schematic diagrams and etc then you can go ahead to repair it.
Okay back to this article, among my customers had asked me to repair his ATX power supply. I told him to acquire a new one (since it absolutely was very cheap) but he explained he couldn’t find the one that suits his customer’s CPU. He wanted a power that is either same size or smaller then your original one with same or maybe more specification but all he may find was a typical size power supply!
As a favors to my customer, I would do my best to help him to repair the ATX power supply. When the ability supply was activate, measurements were taken. The outcomes were over voltage. The 12 volts line shot up to 13 + volt and the 5 volts line became 5.6 volts. Following the casing was removed, I discovered the interior was very dirty and I used a vacuum and a brush to wash off the dirt. Then I saw four filter electrolytic capacitors had bulged at the top casing.
Everbody knows, we as electronic repairers can’t just see things at just one side; we’ve to see the other sides too. What I am talking about was, make an effort to see if you can find any suspicious components that contributed to the failure of the ability supply such as for instance broken components, dry joints, loose connection, decay glue and etc before start checking the suspected area.
What I saw was at the principal side there were some components covered with decayed glue as observed in the picture. I need certainly to carefully remove it by scrapping off the layers of the decayed glue while preserving the outer layers of the components. Once it absolutely was done, I clean it with the Thinner solution. Decayed glue could cause serious or intermittent problem in electronic equipment because it may be conductive.
In the event that you repair any ATX power supply, be sure you check the fan too because some power supply failure was as a result of heat the result of a faulty fan. The goal of the fan would be to suck out all heat generated by the components inside the ability supply. For the fan to run smooth, you can service it using a Philips oil base spray as shown in the photo.
After the four electrolytic capacitors were replaced and the decayed glue removed, I then need certainly to plug it in to a junk motherboard along with a hard disk to try the performance of the ATX power supply and measure each of its output voltages. It looks like the output voltages were back to normal. Once everything is okay I then test drive it in a working CPU to check on for the display.
The reason I test drive it with a junk motherboard first as an easy way to not cause my good motherboard to go south in case if the output voltages continues to be very high. Better safe than regret later. Incidentally you can’t test a power without load otherwise it may turned on for a time and then shut down. If you may not have a junk motherboard you can always at least connect a hard disk and a line jumper to its connector to turn on the ATX power supply.