
But thermal electrical contacts (1)-related concepts and definitions
- Time:2016-11-28 00:00
- Visits:
(Summary description)1. Power system: from power generation, transmission, and power supply to the "wired" connection network at the end of the electricity consumption. Airplanes, warships, trains, automobiles, satellites, space stations, national power grids, local independent power grids, etc., regardless of power source form, voltage level, or network size, are each a type (a) power system.
But thermal electrical contacts (1)-related concepts and definitions
(Summary description)1. Power system: from power generation, transmission, and power supply to the "wired" connection network at the end of the electricity consumption. Airplanes, warships, trains, automobiles, satellites, space stations, national power grids, local independent power grids, etc., regardless of power source form, voltage level, or network size, are each a type (a) power system.
- Categories:Disruptive Idea
- Author:
- Origin:
- Time of issue:2016-11-28 00:00
- Views:
1. Power system: from power generation, transmission, and power supply to the "wired" connection network at the end of the electricity consumption. Airplanes, warships, trains, automobiles, satellites, space stations, national power grids, local independent power grids, etc., regardless of power source form, voltage level, or network size, are each a type (a) power system.
2. Electrical contact: In the power system for power generation and supply, an electrical contact (joint) is formed where two current-carrying conductors (wires) are connected. In the past, electrical contacts, contacts, terminals, connectors, etc., referred to by various industries and units are collectively referred to as electrical contacts. According to its connection form, it can be divided into three categories: split-combination type; relative movable type; disassembly type electrical contacts.
3. The electrical contact is overheated: the temperature of the electrical contact is higher than (equal to) the temperature of its conductor (line).
4. Overheated electrical contacts: electrical contacts whose temperature is lower than the conductor (wire) temperature by more than 5%.
5. Overheating of electrical equipment: The overheating of electrical equipment (cables, conductors, wires) is mainly caused by the heat generated by the current. If the wire is 70°C, the upper oil temperature of the transformer is 85°C, etc., the electrical equipment is overheated if it exceeds this specification. Obviously, this is not the same as the overheating of electrical contacts. Don’t confuse the theory that the electrical contact temperature is lower than the temperature of its conductor (wire) by saying that the electrical equipment must generate heat and exceed the regulations as overheating. Concept.
6. Effective current-carrying cross-sectional area: After long-term energized operation, the contact surface through which current passes under thermal and dynamic stability. The original contact surface is not completely equal to the effective current-carrying cross-sectional area.
7. "Surface phenomenon" of overheating of electrical contacts: oxidation and corrosion of contact surfaces of electrical contacts (electrical, chemical corrosion).
8. "Causes" of overheating of electrical contacts: The pressure on the contact surface of the electrical contacts is reduced, the effective current-carrying cross-sectional area is smaller than the conductor (line), and the resistance at the electrical contact is greater than the resistance of the conductor (line).
9. The "main contradiction" of overheating of electrical contacts: The metallic fatigue of electrical contacts (fasteners) is the "main contradiction". It causes the pressure on the contact surface to decrease, and the effective current-carrying cross-sectional area is reduced. The resistance at the electrical contact is greater than the resistance of the conductor (line) of the same length, and the electrical contact (joint) is overheated to cause oxidation and corrosion of the contact surface. Be careful not to think that oxidation and corrosion cause electrical contacts to overheat.
10. A trilogy to test whether the theory and technology of "not hot electrical contacts" are correct: First, the truth should be equally valid in all types of power systems; second, it can withstand the test of practice, the so-called practice It is the standard for testing truth; finally, it needs to be proved by history. History has proved that the people recognize that it is correct, and that is the truth, and it is by no means determined by which authority.
11. Whether the scientific and technological achievements are the standard of progress: promote the development of the national economy, increase productivity, and produce huge safety benefits, economic benefits and social benefits, especially to ensure that people's lives and property are protected from damage.
12. Propaganda and promote the 16 principles of "not too hot electrical contacts": awareness raising, concept change, technology implementation, and training in place.
13. Completely eliminate the four basic principles of "electrical contact overheating": the theory of "electrical contact overheating". (slightly)
14, six requirements: "not too hot electrical contacts" technology. (slightly)
15. The correct inspection method for overheated electrical contacts: 1.5-2 times the rated current, after half an hour of testing, the temperature at the electrical contacts should be more than 5% lower than the conductor (line) temperature.
16. The revolution of electrical contacts: From the concept of "electric contacts overheating" to the road of "overheating electrical contacts".


119 Safety and firefighting must be done practically. "Superconductivity" cannot solve man-made disasters such as electrical fires!

Pay special attention to the power safety revolution forum, and Mount Everest discusses electricity-to solve the mystery of a century of electrical disasters in the world of man-made disasters! Solve and eradicate the global ...

Special attention should be paid to national power safety in summer
ADD
128 Hongyang East Road, Qingbaijiang District, Chengdu
CHENGDU BRANCH
Room 3101, Tower 2, Raffles City, Wuhou
District, Chengdu,PR China
Copyright © 2022 Sichuan Renyi Electric Co., Ltd. 蜀ICP备12025125号 Powered by:www.300.cn SEO