How to repair the power supply unit?

The power supply is a very important component of the computer, without which personal devices can not receive power. This component often fails, while the repair of the power supply can be tried at home. There are pulsed and linear varieties, the principle of operation and arrangement of which differ. The linear unit consists of a stabilizer, a diode bridge and a transformer. In a pulse device, the voltage for powering the generator is rectified by a diode bridge, and then removed from the high-frequency transformer for further output.

The power unit is repaired using tools such as a Phillips-head screwdriver, a soldering iron, a multimeter with a bump of transitions. In addition, a set of resistors, a hard drive or a motherboard will be required, an oscilloscope and an additional (12 V) power supply can also be used. It should be borne in mind that it is forbidden to switch on a pulse device without load.

In stationary computers, ATX power supplies are most often installed, the repair methods of which are quite distinct.

Firstly, if the device fails, check the voltage on the board. If there is none, then you should look for a break before payment. It can be in the interference filter, the switch, the wires, the socket may be faulty. If everything is OK, then check the voltage supply after the diode bridge. Then, when repairing the ATX power supply, check the fuse, the resistance of which should tend to zero.

Next, watch the varistor (is there any current after it). This is easier to do with the device turned on. If the power supply is of high quality, then it includes smoothing current chokes, whose winding resistance should approach zero.

At the next stage, the repair of the power supply includes checking the status of the diode bridge with the computer turned on. An alternating current must be applied to it , and a constant current must be output . Otherwise, the diodes are faulty.

Very often the cause of the failure of the device is the failure of the capacitors. If they flow or swelled, then the repair of the power unit is to replace these elements. The work of high-voltage transistors can be checked using a multimeter.

In general, troubleshooting a computer, like repairing a power supply for a TV, requires special knowledge and skills. It is not enough to have a general idea of the operation of these devices. Therefore it is better to contact specialists in the service centers. Sometimes the cost of work can exceed the price of a new power supply. Thus, it should be estimated that it is more profitable to repair or simply replace the faulty unit.

Determine that the unit has failed, can be closed by black and green contacts (from the connector to the motherboard). If, after connecting these wires, for example, with a clip, the fan of the unit does not work, then the device most likely failed. You can connect the contacts only when the device is disconnected from the network!