How to repair the computer power supply? How to fix a broken computer power supply

Computer power supply maintenance requires a certain amount of electronic professional knowledge to be repaired, and the tools needed are electric soldering irons, changing cones, multimeters, solder suckers and false load bulbs.

The maintenance method is to disassemble the power supply with a change cone, first visually check whether there are obvious damaged components, replace the damaged components, and then use a multimeter to check whether there is a damaged original from the power input terminal, and remove and replace it after finding the damaged original. Until all the broken originals are replaced. Then, remove the power supply insurance, connect the false load to the power supply between the two safety sockets, plug in the power supply, short the green and black lines of the power supply, see if the power supply can start, if the light is on, the power supply still has a short-circuit fault, it needs to be overhauled again, if it is not on, it means that the power supply has no major short-circuit fault, you can try to measure whether the output of each group is normal, normal means that the power supply is rare repair, connected to the computer, can be used normally, it means that it has been OK, no, it needs to be overhauled.

Try the motherboard of the computer with other power supplies first, it is not necessarily that the power supply is bad, it is usually a motherboard problem.

If it is a power supply problem, is the load rate of the power supply too low and the load cannot be moved, first determine that it has the ability to repair with electricity? There are certain tools at home, circuit diagrams, loads, high-power power switches, etc.

Plug in the 220V power supply, there is a 5V voltage output on the purple line, indicating that the primary transformer side is good, the load is low but can be started, usually the output rectifier diode is bad, the power of the excitation tube is insufficient, (the switch tube burns out and cannot be started), and so on, ,--etc

Power-on maintenance is dangerous, need 220V isolated power supply to be repaired, it is not recommended that people who do not have much experience repair themselves, throw it away, collect 5 yuan for the computer, buy a good second-hand Huntkey rated 300W power supply is only 40, and the miscellaneous brand is only 20 yuan.

Hello dear, I found out that the repair method of the computer power supply is as follows: 1. Short circuit 1. The current causes the diode or capacitor to be broken and the fuse will be blown out. 2. In either case, it is basically caused by excessive voltage.

3. At this time, we can replace the damaged equipment and replace it with a more pressure-resistant switch. 2. Fuse blowing 1. If the fuse is blown but does not turn black, it means that it is not caused by a short circuit. 2. Then there is a high probability that it is caused by excessive load.

3. We can first confirm whether there is damage, replace the fuse if not, and then try not to overload it when using. 3. No self-test when booting 1. If the power supply has output, but it cannot be turned on due to no self-test. 2. You can try to use a voltmeter to measure whether there is current at the output end of PW-OK.

3. If there is no indication that it is broken, if there is, it may be that the delay is not enough, and you need to check whether the resistance is normal. 4. The fan does not rotate or the noise is loud 1. Check whether the fan is damaged or has too much dust. 2. If not, check whether the surrounding screws are loose or falling.

3. Confirm whether there is current, if not, then the power supply cannot be output. 4. If there is no current, then the motor is broken and the motor needs to be replaced.

Repairing a computer power supply requires an electrician with weak current work qualifications and supporting electrical equipment, rather than a question that can be solved.

Use a multimeter to measure the forward and reverse resistance of both ends of the AC power line and the charging of the capacitor, if the resistance value is too low, it means that there is a short circuit inside the power supply (the resistance value should reach more than 100 thousand ohms under normal times); The capacitor should be able to charge and discharge, if it is damaged, it will be manifested as a low resistance at both ends of the AC power line, and it will be in a short-circuit state, otherwise it may be a switch triode VT1, VT2 breakdown. Then check the DC output section. Disconnect the load, measure the resistance to the ground at the output end of each group respectively, when normal, the gauge hand should have a capacitor charge and discharge swing, and the last indication should be the resistance value of the discharge resistance of the road.

Otherwise, it is mostly caused by the reverse breakdown of the rectified diode.