Description
A Power supply unit (PC Power supply unit, PSU or power supply) is the power supply for all components of a computer. Hong Kong is also known as the fire cow, (is the electric cow also, the power supplier, from the early transformer shaped like a cow). A power supply is a power conversion type of computer (as opposed to battery powered power supply), responsible for converting standard alternating current into low-voltage stable direct current for use by other components in the computer. Generally, computer power supplies are switched power supplies, and the input voltage automatically ADAPTS to the user's local utility parameters (while some products may require the user to adjust the voltage switch). Computer power transfers alternating current from a wall outlet to low-voltage direct current for computer processors and peripherals. Because different components require different voltages, the power supply needs to provide several DC voltages; The components in the computer need a stable and continuous DC voltage, so the power supply must be equipped with a voltage regulator/stabilizer (regulator) to provide accurate and stable voltage values to ensure the normal operation of the computer components. The terms "power supply rail"/" power supply rail "or" voltage rail "/" votage rail "generally refer to the various voltage values provided by the power supply. Although the term is often used in electronic engineering, many people, especially computer enthusiasts, will encounter these terms when they come into contact with and deeply understand PC power supplies. The power supply for the first generation of microcomputers, home computers, was a linear power supply consisting of a heavy step-down transformer combined with a rectifier, a filter assembly, and a regulator. Modern computers use switching power supplies (SMPS) : after the mains is rectified and filtered directly, the isolated DC-DC conversion device composed of a high-frequency switching device (such as a power level BJT or a power level MOSFET) and a ferrite core high-frequency step-down transformer reduces a number of DC voltages, and then outputs the electrical energy for computer use by a voltage regulator and filter device. Switching power supplies are much lighter, less costly, and more efficient than equivalent linear power supplies.
Many computer power supplies are also equipped with short-circuit protection, overload protection, overvoltage protection, undervoltage protection, overcurrent protection, temperature protection and other functions to ensure the normal and stable work of the power supply and its power supply equipment, many of which are listed as industry standards. In addition, some of the more powerful power supplies, will also be equipped with passive (passive) or active (active) power factor correction (PFC) technology, and this has become the industry standard. The passive power factor correction is usually implemented by inductance capacitance compensation circuit or valley filling circuit, and the power factor can usually reach 0.7 to 0.9. Active power factor correction is more complex but can achieve a high power factor up to 0.99. In order to control the heating of the power supply, there are also lower limits on the power conversion efficiency, such as the 80 PLUS specification certification of informal industry certification.
Modern power supplies are equipped with a standby function, so that the computer can be safely shut down through the operating system. Since the power supply still provides voltage after the system is turned off, as long as the motherboard supports it, the switch key can be triggered to boot, LAN wake up to boot, computer keyboard and mouse wake up to boot and so on.
The total fixed output power of the power supply is limited by the rated output power of each voltage channel separated from the same high-frequency transformer, as well as the parameters of key components such as the maximum current capacity of the power stage FET or BJT/GTR. The power requirements of personal computers are also very wide, from low-power platforms under 250W to multi-graphics/multi-CPU platforms over 1000W. The common power supply, the rated power is generally between 300W and 500W. Power supplies are generally designed to have a power margin of 40% more than the calculated theoretical "system maximum power" value, both to avoid degradation of system performance and to cope with possible unexpected heavy loads. The total power output is also marked on the power supply (some are marked with rated power, but some are marked with maximum peak power, note that the former is generally subject to), or the maximum current limit of each voltage channel is also marked. Some lower-end power supplies may castrate heavy-duty protection components and circuits for profit.
The maximum power consumption required by the computer system is determined by the sum of the maximum electrical power required by the active components in the computer (graphics card, motherboard, CPU, memory, hard disk drive, cooling fan and other components that require electrical energy to work), and computer manufacturers, building machines /DIY users need to choose a power supply according to this. For large power consumption - graphics cards, the rated output power/maximum output current of the 12V output channel of the power supply must be paid attention to. Manufacturers of computer active components, especially graphics card and motherboard manufacturers, will indicate on their instructions how many watts of power they need to be rated. In addition, the thermal design power consumption (TDP) value of cpus and graphics cards is also used as a reference for power supply selection from time to time, but it should be noted that TDP is not equivalent to the actual power consumption of components, and TDP is mainly used as a required parameter for radiator selection. On hard drives and optical drives, there are generally clear parameters for rated input voltage and maximum current required.
The rated power is not only a parameter pointer of the power supply, but also one of the publicity points of the manufacturer. Some power supply manufacturers will claim that their products have how much output power, but often the actual rated output power will be low, and the worse is even less than half of the declared value. To make things more complicated, some of the power supply's 5 volt voltage channel is obtained from the 12V voltage channel step-down, if the current capacity of the 12V channel is insufficient, or the voltage regulator circuit current capacity of the 5V channel is insufficient, it will cause the 12V channel or 5V channel to be overloaded when it is far from the nominal total power of the power supply.
In addition, there are 3.3V voltage channels from the 5V voltage channel, or non-isolated DC-DC scheme, 5V, 3.3V channels from the 12V channel design, at this time the maximum current of 5V and 3.3V channels will be limited by the maximum current capacity of the 12V channel. For example, the 3.3V channel takes power from the 5V channel, the 3.3V channel has a current capacity of 10A (that is, has 33W output power), and the 5V channel has a current capacity of 20A (that is, 100W output power), but if the combined output power of the two is only 110W, then, When the 3.3V channel reaches the maximum output power of the channel, only 77W can be maximum output on the 5V channel.
The company focuses on DCS, PLC, robot, large servo four systems
The main products are various modules/cards, controllers, touch screens, servo drivers
Company advantage: Supply imported original products, professional production of spare parts
One year warranty, fast delivery time, complete supply !！！
① 24 hours email response (12 hours);
② For shipment outside Asia, please contact the seller.
【 Disclaimer 】 We sell new products and discontinued products, independent channels to buy such special products. Guizhou Yuanmiao Automation Equipment Co., Ltd. is not an authorized distributor, dealer or representative of the products featured on this website. All product names/product images, trademarks, brands and microlabels used on this Website are the property of their respective owners. Descriptions, depictions or sales of products with such names/images, trademarks, brands and logos are for identification purposes only and do not imply any association or authorization with any rights holder. This article is from the official website of Guizhou Yuanmiao Automation Equipment Co., LTD. Please attach this link:https://www.ymdcs.com/Fanuc/
