How Do I Choose the Best Computer Power Supply?

Computers are weak electric products, which means that the working voltage of the components is relatively low, generally within plus or minus 12 volts, and is direct current. The ordinary mains power is 220 volts (110 volts in some countries) and cannot be used directly on computer parts. Therefore, computers, like many home appliances, need a power supply part, which is responsible for converting ordinary mains power to a voltage that can be used by the computer, and is generally installed inside the computer. The working voltage of the core components of the computer is very low, and because the computer operates at a very high frequency, the power requirements are relatively high. At present, the power source of a computer is a switching circuit, which converts ordinary AC power to DC power, and then choppers the control voltage to output different voltages to computer components such as the motherboard, hard disk, and optical drive.

Computer power

Switching power supply mainly includes input grid filter, input rectifier filter, converter, output rectifier filter, control circuit and protection circuit. Their functions are:

Power supply is the heart of the computer. Poor quality power supply will not only damage the motherboard, hard disk and other components, but also shorten the normal life of the computer. Of course, the price of a high-quality power supply will not be cheap, so some businesses often use cheap power supplies to fool consumers, and some users do nt know much about it, but the difference of dozens of yuan may incur Thousand yuan loss, this is really worthless, so pay special attention to the quality of the power supply when buying.

Safety standards are based on guaranteeing the safety of users' lives and property, and make strict regulations on the insulation and flame retardant of raw materials. Products that meet safety standards not only require the product itself to meet safety standards, but also require a more complete safety production system for the manufacturer. Among these standards, the German VDE-0806 standard based on the 1EC-380 standard is the most stringent. China's national standard is GB4943-1995 "Safety of Information Technology Equipment (Including Electrical Equipment)". The safety of the power supply meets the above standards. The power supply complies with the safety standards of a certain country and obtained a certificate issued by its statutory department, such as obtaining a certificate issued by a UL agency, which is called obtaining

Due to the increasing popularity of ATX motherboards,

So how can you find a suitable power supply in such a chaotic market?

Computer power appearance check

A. Power supply weight. Good power is usually heavier.

B. Power output line. Don't underestimate these output lines, because the output current of the power supply box is generally large, a small resistance will cause a large voltage drop loss. A good quality power supply must be a thick wire. Of course, you ca nt just look at the thickness and appearance of the wire. Many manufacturers can make very small wires thick. You need to look at the wire number on the line. Otherwise, you wo nt be able to pass the safety certification.) There are two Arabic numbers on the line beginning with AWG and this number is the line number. The smaller the wire number, the larger the core, that is, the 16th wire is better than the 22th wire.

Computer power supply heat sink material

Looking from the heat dissipation window of the housing, the high-quality power supply uses aluminum or copper heat sinks, and is larger and thicker.

Computer power supply measures load voltage drop

Select a power supply with a small voltage drop. If it is an ATX power supply, you can leave all the output terminals floating. First measure the no-load output voltage. The method is to make PSON (green line) and GND (black line) short-circuit the start-up power supply, and then measure the output current to about At 10A, the smaller the voltage drop, the better. The above test must not be done on + 12V, -12V, so as not to burn the power supply.

Computer power if the power ground is not connected

The shell is slightly hemp after the high-quality power is turned on. If the voltage cannot be measured, it means that there is no filter screen installed in the inside. In addition, the fan sound is even and small during no-load operation. When the load is connected, the sound will increase slightly when the temperature rises slightly.

Computer power on power box

It can be found that high-quality power supplies are exquisite, such as using square CBB capacitors in multiple places, the input filter capacitor value is greater than 470 microfarads, and the output filter capacitor value is also large. At the same time, there are many internal inductor and capacitor filtering network circuits, and there are perfect overvoltage and current limiting protection components.

A qualified power supply should pass safety and electromagnetic certifications, such as meeting CCC / TUV / CE / UL (eg, GB4943-95 "Safety of Information Technology Equipment (Including Electrical Affairs Equipment)"; GB9254-88 "Information, Technology Radio interference limits and measurement methods for equipment "; GB17625.1-2003" Electromagnetic Compatibility Limits and Harmonic Current Emission Limits ") and other standards. The certification marks of these standards should be marked on the exterior of the power supply with their special icons .