My apprehension level would go up several notches whenever I was called upon to do computer power supply repairing work…
Listen, I know that sounds crazy but seriously… I used to hate troubleshooting and fixing power supply! You want to know why?
Alright look, I'm sure you're aware that computers these days are powered using switch mode power supplies (abbv. as SMPS), right?
Well, the circuit designs of SMPS were excruciatingly hard to figure out!
However for the past few months, I've done more than 2 dozen computer power supply repairing gigs.
I've patched up all sorts of SMPS problems so I'm no longer apprehensive about repairing them (credit goes to this SMPS repairing manual).
What about you? Still feeling apprehensive about troubleshooting and repairing computer SMPS?
Look, don't worry okay. I want you to focus on the checklist below to ensure you're on the right path…
The Checklist
Did you accumulate all the tools needed to conduct computer power supply repairing and troubleshooting in the proper manner?
For testing purposes, the most vital tool is volt-ohm meter (abbv. as VOM). You'll be using it regularly, but don't neglect other tools of the trade!
You'll also need the isolation transformer, AC ammeter, digital capacitance meter, oscilloscope, variable transformer, UC3842 power IC tester etc for testing and reparation purposes.
Did you perform the proper voltage measurement to determine if overvoltage is the primary cause of issue?
It's important you take a few measurements to absolutely determine that overvoltage is the main problem.
Take a look at the 12 and 5 volts line. If the numbers are higher than indicated, then you have an overvoltage problem on your hands.
Did you inspect individual components in a thorough fashion?
The filter electrolytic capacitors are pretty fragile thus they get easily damaged. So you really need to inspect them properly. Another component that should you lookout for is the dual schottky barrier rectifier.
Get your analog meter ready and put the setting to X10 K ohms. Next do a reverse bias test to find out if there's leakage reading.
Did you download a computer power supply repairing manual that helps you every step of the way?
I suggest you get a copy of SMPS repairing manual that contains full instructional photos. You can use it again and again to assist you in repairing various types of SMPS.
The one I use can be found by clicking this link.
