If the electrical contact (joint) temperature is higher than (equal to) the temperature of its conductor (line), the "electric contact overheating" fault (at this time "line loss" has already occurred), if not found early, the resistance at the electrical contact is greater than the same length The resistance of the conductor, the temperature further rises, and a vicious cycle will cause electrical contacts (joints) to burn red, equipment burned, short circuits, power supply interruptions, electrical fires, planes, train crashes, and automobiles "spontaneous combustion", even directly endangering citizens with electricity Safety of life and property. For many years, the overheating of electrical contacts (joints) has become a difficult problem for the safe production, energy saving and consumption reduction of various power systems at home and abroad, and the concept of "electric contacts overheating" has almost become a "trend". In fact, as long as the temperature of the electrical contact (joint) is lower than 5% of the temperature of its conductor (line), the above problems can be solved.

In my more than 40 years of production practice, I have also historically and traditionally believed that electrical contacts (joints) are the weak parts of the circuit and are important parts of overheating; what oxidation and corrosion (chemical, electrical corrosion) cause electrical The contact is overheated; even the contact resistance of the busbar connector is generally not more than 20% of the resistance value of the busbar of the same length, etc. Under the guidance of the theory and concept of "electrical contact overheating", the "surface phenomenon" of oxidation and corrosion will be As the “main contradiction” of overheating of electrical contacts (joints), I kept repeating past mistakes. After hitting the south wall, after a number of reasonable suggestions, small changes and small leathers could not completely eliminate the overheating of electrical contacts. In the processing of GW4-35/2000 isolation switches and bolt-type equipment clamps, it was found that the "main contradiction" of the overheating of the electrical contacts of "copper-aluminum metallic fatigue" was hidden by the surface phenomenon of "oxidation and corrosion". It causes the pressure on the contact surface to decrease and the effective cross-sectional area of ​​current-carrying is reduced (cause of overheating). It is precisely because the "main contradiction" of electrical contacts (joints) overheating is grasped that there are fewer overheating failures of electrical equipment that has just been put into the power system. With the increase of operating time, there is a reasonable explanation for frequent accidents. . This is a common problem that is ignored by scientific research departments in books, education and training, design and manufacturing, installation and operation, but it is a problem that exists in production practice.

After continuous exploration, repeated testing, and continuous improvement, the patented products from small reforms to utility models have been widely promoted and used by customers in many provinces and cities across the country. They were used in Beijing for the fifth session in 2005 and Guangzhou for the sixth session in 2007. Articles were published at international conferences and were affirmed by the China Electricity Council. In 2007, the temperature of the electrical contact was measured at twice the rated current at the Sichuan Electric Power Test and Research Institute. The temperature of the electrical contact was 20% lower than the temperature of the busbar. Then, the temperature of the electrical contact (joint) was lower than the temperature of its conductor by more than 5%. The contact definition is established. And the inspection method for electrical contacts is also set to 1.5-2 times the rated current for more than half an hour to measure the temperature.

The scientific and technological achievements of "Overheating Electrical Contact Research" and "Special Fasteners for Overheating Electrical Contacts" Chuankejian Zi [2011] No. 018, National Science and Technology Achievement Network 9512011Y0026, and the invention of "a kind of elimination of electrical "Methods of overheating of contacts", 201010545987.7; PCT/CN2010/079856, which contains the "four basic principles" theory of eliminating overheating of electrical contacts and the "six requirements" technology for overheating electrical contacts, will be gradually published in the blog Introduce to all the insightful people in the power industry who care, support, and strive for change, as well as the vast number of citizens who use electricity, let us work together to completely eliminate the overheating of electrical contacts, the "beneficial merit"!