how to fix computer power supply

 

Practical ways to improve the computer's power supply could be made as follows: 

 

[1]. Disconnect the power supply box for easier checking of Cassing electronic circuits and disconnect all cables from other tools. Open the box, checking the physical power supply electronic components, perhaps there is a fire can be known.

[2]. Check the insert FUSE 220V AC power source from outside, remove it from the socket FUSE and measuring the safety wire ties with ohm-meter at the position X1. Ohm-meter needle should indicate a value of about 0 ohms, which means that FUSE is still good. If the ohm-meter showed an infinite number, it means that FUSE has been broken, must be replaced. Do not make the connection wires on FUSE is already broken, because the melting current limit will probably be larger and will cause damage to other parts.

[3]. If FUSE either new or have been replaced but still can not remove the DC voltage, then proceed by examining the power switching transistor 2SC3039 (two pieces), which served as the control of a PWM power supply. Remove the two 2SC3039 transistor from the PCB and do check the condition of each with a multimeter. If one transistor should be broken to replace both of them replaced with new transistors, so guaranteed and symmetrical characteristics, the imbalance characteristics of the two transistors is causing interference issued stability DC voltage power supply.

[4]. Remove the diode bridge rectifier or four diodes which leveled directly at the AC electrical currents enter, check the condition of this diode with a multimeter. Sometimes this happens one of his diodes leak or short-circuit, so that the AC power coming in to the circuit switching and disabling the entire power supply will power transistors were damaged, burned. Even if the rate of leakage of this diode is very large, then it will melt the switching transformer, wire peeled off, and connected short, is the most fatal damage.

[5]. Check also the transistor pulse generator "power on reset", also contained kapasisitor and resistors in the circuit of the transistor base. If the transistor circuit is working properly, then the whole result a DC voltage regulation will be reset by the PWM generator and consequently did not issue a DC power supply at all. Replace the new transistor if the transistor POR testing proved defective. So, when the capacitor in the test will be dry, its value is changed, then it should just be replaced with the exact same value as before.

[6]. Because the computer power supply generally work with a higher temperature than room temperature, then there is a possibility because of the excessive heat causes the solder legs of components or cables are loose. Check the solder on the PCB Power Supply, make sure to do even better in improving the way in re-solder with a softer tin (dilute, fluxes 60/40). So that the cable connection or leg components may be loosely knit and guaranteed power supply will generally be able to work normally again.

[7]. Pengetesannya active component can not be done with a multimeter is ICTL494 who served as a PWM generator to control the power switching transistor works. IC is only in the test by comparing to the IC power supply is normal in the other kind. Use IC sockets with a suspected broken comparator IC is still good.

[8]. When the process of inspection and replacement of defective parts could have been done as a whole, then try the power supply is turned on by placing the burden of drine disk only. Check whether the fan spinning, measuring voltage cable yellow (+12), red (+5), blue (-5), blue (-12), orange (POR) to black wire (ground). When the parameters of the voltage on the cables are correct, turn off the power supply and replace the motherboard or a load with a full load as before, try again.