Full analysis of power supply certification standards
In today's digital age, computers have become an indispensable tool in people's lives and work. As the number of devices connected to a computer is increasing day by day, such as high - performance graphics cards, large - capacity hard drives, and various external devices, the energy consumption of the computer is also constantly increasing. This is like a big family: the more members there are, the more resources are consumed. And the power supply is like the "energy supply station" of this family, providing stable power support for each component of the computer. If the power supply has insufficient power, just as the energy of the supply station is not enough to meet the needs of the family, it may cause damage to important components of the computer, such as the motherboard and hard drive, due to unstable power, thus greatly shortening the normal service life of the computer.
Currently, the power supply market is full of a wide variety of products. In terms of price, there are products ranging from low - cost ones priced at dozens of yuan to high - end ones costing over a hundred yuan. Facing such a large number of choices, consumers are often confused and don't know how to select a high - quality power supply. In fact, an important basis for judging the quality of a power supply is its safety certification status. Generally speaking, the more certification items a power supply obtains, the higher the reliability of its quality in all aspects. This is just like a person who has won more honors, indicating that his ability and quality in the relevant field are more trustworthy. Therefore, when purchasing a power supply, we should try to choose products that have obtained more certifications.
Detailed Explanation of Power Supply Certification Projects
CCC Certification
CCC certification, fully known as "China Compulsory Certification", is like an "admission ticket" for power supply products entering the Chinese market. Currently, there are two versions of CCC certificates, namely CCC (S) and CCC (S&E). Among them, CCC (S) only indicates that the power supply has passed the safety standard test. However, the validity period of this version ends on April 30th next year. That is to say, after this time point, power supply products only holding the CCC (S) certificate will not be allowed to continue to be sold in the market. In contrast, CCC (S&E) means that the product has obtained both safety and electromagnetic compatibility certifications. It's like a person who is not only physically healthy but also able to get along harmoniously with the surrounding environment. Power supply products with the CCC (S&E) mark can still be sold in the market after May 1st next year.
The state has clear institutional regulations regarding the CCC certification. According to the "Notice on Issues Concerning the Implementation of the Compulsory Product Certification System" (Guo Ren Zheng [2001] No. 30) issued by the Certification and Accreditation Administration of the People's Republic of China, the new national compulsory certification system began to be implemented on May 1, 2002, and was enforced starting from May 1, 2003. Since then, the new CCC certificates have been used. The old certification systems, such as CCEE and CCIB, were abolished as of May 1, 2003, and the use of relevant old certificates was stopped. From May 1, 2002, to April 30, 2003, it was a period when the old and new certificates coexisted. During this period, the CCEE and CCIB certification work was stopped.
FCC Certification
The FCC certification is a certification regarding electromagnetic interference. As we know, when the power supply is working, strong electromagnetic interference will be generated inside it. This is like a bustling marketplace where various sounds are intertwined, forming a noisy interference. If these electromagnetic interferences are not shielded, they may be like naughty "little monsters" and have an impact on monitors, motherboards, and other electrical equipment. For example, it may cause the monitor screen to flicker, the motherboard to work unstably, etc., and may even bring harm to the human body. Just as long - term exposure to a noisy environment can affect people's hearing, long - term exposure to electromagnetic interference may also have an adverse impact on human health.
To regulate electromagnetic interference, there are strict international regulations. The common standards are the FCC - A industrial standard and the FCC - B civilian standard. The FCC - A industrial standard is applicable to industrial environments and has relatively looser restrictions on electromagnetic interference. In contrast, the FCC - B civilian standard is more stringent because it is designed to ensure the safety of ordinary consumers in daily use. Only power supplies that meet the FCC - B civilian standard can be considered safe and harmless, just as only food that meets the hygiene standards can make people feel at ease to eat.
UL certification
UL, namely Underwriters Laboratories, is the most authoritative and non - profit private safety testing institution in the United States. It is like a strict "quality inspector", mainly conducting safety tests and inspections on various equipment, systems and materials. Its purpose is to confirm whether these products pose a danger to life and property and make the inspection results public. This is just like a fair referee truthfully informing the audience of the game results.
UL has published hundreds of standards, most of which have been adopted by ANSI (American National Standards Institute). Generally speaking, UL standards cover multiple aspects, including:- Requirements for product structure. Just like building a house, a reasonable structure is needed to ensure safety.- Requirements for the raw materials used in products. The quality of raw materials directly affects the performance and safety of products.- Requirements for the components used in products. Components are like various parts in a house, and their quality is of crucial importance.- Requirements for testing instruments and testing methods. Accurate testing can yield reliable results.- Requirements for product labels and instruction manuals. Clear labels and instructions can enable users to use products correctly.Now, UL certification has become one of the strictest certifications globally. Power products that have obtained UL certification have relatively high guarantees in terms of quality and safety.
CSA certification
CSA is the abbreviation of the Canadian Standards Association. It is Canada's first non - profit organization dedicated to developing industrial standards and is also one of the world's most famous certification bodies. In the North American market, for products such as electronics and electrical appliances to be sold smoothly, they must obtain CSA safety certification. This is just like having to hold a corresponding membership card to enter a specific club.
The CSA standard mainly stipulates the testing methods for products, processes, and materials, as well as the safety of services and materials. It is like a comprehensive "rule book" that covers every aspect of a product from production to use. Power products that have passed the CSA certification enjoy high recognition and competitiveness in the North American market.
CE certification
CE is the Latin abbreviation for "European Union". It is a mark for qualified products introduced by the EU to certify that products meet its specified requirements. The CE mark is like a "mandatory pass" for products to enter the EU market, and it is also one of the basic certification standards for power supply production and manufacturing. The EU requires that power supply products with the CE mark must protect the health and safety of users and meet basic environmental protection requirements. This is like a person entering a certain community, who not only has to abide by the community's safety regulations but also take good care of the community's environment. Only power supply products that have obtained CE certification can be legally sold in the EU market.
Key indicators for assessing the power supply
Generally speaking, there are many safety certification standards for power supplies. Among them, the VDE - 0806 standard formulated by Germany based on the 1EC - 380 standard is considered to be the strictest. China also has its own national standard, namely GB4943 - 1995 "Safety of Information Technology Equipment (Including Electrical Equipment)". Although these standards are formulated by different countries, most of them make strict regulations in several aspects such as creepage distance, dielectric strength, leakage current, temperature, and electromagnetic interference.
Requirements for creepage distance
Creepage distance refers to the shortest distance measured along the insulating surface between two conductive devices or between a conductive device and the equipment interface. The safety standards of UL, CSA, and VDE all strongly emphasize the safety requirements for creepage distance. This is because if the creepage distance is too short, arcing may occur between devices or between a device and the ground, just like an electric spark is generated when two charged objects get too close to each other, which poses a threat to personal safety. Therefore, a reasonable creepage distance is one of the important factors to ensure the safe use of the power supply.
Requirements for electric strength
Withstand voltage is a performance indicator that measures the power supply's ability when subjected to voltage. Between the AC input lines or between the AC input and the chassis, when the voltage is gradually increased from zero to 1500V AC or 2200V DC, if the power supply does not experience breakdown or arcing, it indicates that the withstand voltage of the power supply meets the requirements. This is like a person being able to withstand a certain amount of pressure without being crushed. The withstand voltage of the power supply is also the key to ensuring its normal operation in a high - voltage environment.
Requirements for leakage current
Both UL and CSA require that all exposed, non - energized metal parts should be connected to the ground. The measurement of leakage current is carried out by connecting a 1.5kΩ resistor between these parts and the ground, and then measuring the leakage current. For a switching power supply, at an AC input of 260V, its leakage current should not exceed 3.5mA. If the leakage current is too large, it may pose a risk of electric shock to the human body and may also affect the normal operation of the power supply. Therefore, strictly controlling the leakage current is an important measure to ensure the safety of the power supply.
Temperature requirements
Safety standards attach great importance to the temperature requirements of electrical appliances and also require materials to have flame retardancy. For a switching power supply, its internal temperature rise should not exceed 65°C. If the ambient temperature is 25°C, the temperature of the power supply's components should be less than 90°C. This is because excessive temperature will affect the performance and service life of the power supply. Just as people are prone to getting sick in a high - temperature environment, the power supply is also prone to malfunction at high temperatures. Moreover, a power supply that does not meet safety standards may not have any direct adverse effects on users at the beginning of use. However, over time, due to the influence of humid air and dust, it may cause a short - circuit in the high - voltage area. This will not only damage the power supply itself but also seriously affect the power grid, thus having an adverse impact on other electrical appliances.
Requirements for electromagnetic interference
The internationally recognized electromagnetic interference standards are FCC - A (industrial standard) and FCC - B (civilian standard). The power supply should meet the civilian standard. Electromagnetic interference is divided into conducted interference and radiated interference. Conducted interference is transmitted through the power cord, with a frequency below 30MHz, and mainly interferes with the audio frequency band. Since the switching power supply for computers is shielded by a metal case, the power supply interference is more manifested as conducted interference. The magnitude of conducted interference is an important criterion for measuring the quality of a computer power supply, which includes two aspects: Firstly, it is to prevent the electromagnetic interference on the power grid and the electromagnetic interference generated by the power supply itself from entering the power grid and affecting the normal operation of the host system; Secondly, it is to prevent the electromagnetic interference generated by the host itself from entering the power grid and affecting other electrical appliances. In daily life, we may all have had such experiences. When a microcomputer is turned on, electrical appliances nearby, such as TVs and stereos, may malfunction. This is the impact of conducted interference. Therefore, effectively controlling electromagnetic interference is very important for ensuring the quality of the power supply and the normal operation of surrounding electrical appliances.