Research on CB level ATSE composed of the most exe

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Research on CB level ATSE composed of circuit breakers

Abstract: Taiyong technology has conducted in-depth research on CB level ATSE of various brands at home and abroad, and the company has also developed CB level ATSE based on circuit breakers. In the process of R & D, manufacturing and user use, some problems of CB level ATSE composed of circuit breakers were found. This paper communicated with industry peers, hoping that the industry system can be extended from the shell manufacturing of electronic products to the internal manufacturers of products, and manufacturers can work together, Solve the problems that the accuracy and service life of the sensor will be affected if the accuracy of the strain gauge of CB is not high, or the aging resistance of the glue used to fix the strain gauge is not good, or the material of the sensor is not good, so as to provide the market with CB ATSE with high reliability. Also as a reference for designers

key words: circuit breaker composition CB level ATSE Taiyong technology has conducted in-depth research on CB level ATSE of various brands at home and abroad, and the company has also developed CB level ATSE based on circuit breakers. In the process of R & D, manufacturing and user use, some problems of CB level ATSE composed of circuit breakers have been found. This paper communicates with industry peers and hopes that industry manufacturers can work together to solve the problems of CB level ATSE and provide high reliability CB level ATSE for the market. Also as a reference for designers. Level ATSE concept description: level CB ATSE national standard definition: ATSE equipped with overcurrent release, its main contact can be connected and used to break short-circuit current. 2. Tips: (1) the product can be called ATSE only after it has passed the type test conducted by the organization designated by China Quality Certification Center in accordance with gb/t14048.11 standard and obtained CQC certification. Can distinguish between PC level and CB level ATSE. (2) CB ATSE only requires "short circuit" protection and does not need "overload" protection. With overload protection function will cause many ATSE reliability problems (3) from the product concept, CB ATSE is more powerful than PC ATSE, directly eliminating two circuit breakers and reducing the initial investment. (4) At present, there is no CB level ATSE without circuit breakers in the world. The verification items mainly include the verification of appearance, performance, device inspection and force value. All CB level atses in the market are atses composed of circuit breakers. Among them, there are two operating mechanisms: single electric operation and double electric operation. (5) Designers and users cannot choose ATSE only by product concept. Due to the critical importance of ATSE reliability, we must also fully consider the reliability of products supplied in the actual market. 2. Problems of CB level ATSE composed of circuit breakers: 2.1 there is an inevitable problem of "ATSE conversion function failure when short-circuit protection function works" in practical application: Note: if a short circuit occurs for any reason, the circuit breaker of CB level ATSE trips and cuts off the load power supply, but the controller cannot detect the power failure. Therefore, at this time, CB level ATSE will disconnect the power supply of all loads and need special manual operation to restore the power supply. If there are multiple important loads, using CB level ATSE will lead to the problem that all are responsible for power failure due to a load fault. U.S. ul1008 stipulates that it must be noted on CB ATSE products that if the protection function works, the conversion function will fail. 2.2 CB level ATSE composed of circuit breaker is driven by motor + reducer, and the circuit breaker really trips only when the handle of the circuit breaker needs to be disconnected to a certain position. Therefore, when the common power supply fails, it takes more than 1s for the circuit breaker on the common power supply side to really disconnect, so it will lead to the problem of "the faulty power supply continues to be energized". This will bring problems for some special occasions. 2.3 the circuit breaker has the function of "overload protection", which is not required by ATSE. In practice, if the "overload protection" function works (which often happens), the circuit breaker trips, resulting in the power failure of all loads and the failure of ATSE function. Although it is suggested that the overload protection function can be cancelled to solve this problem, the overload protection function is considered in the design of the circuit breaker, and the overload time of its main contact is strictly controlled. If only the overload mechanism is cancelled, but the material and pressure of the main contact are not changed, then in actual use, if the current exceeds the overload current but does not reach the short-circuit current, the circuit breaker will not trip, When the overload time exceeds the design overload time, the main contact may be burned. Therefore, simply removing the overload mechanism is not a good solution. 2.4 because the circuit breaker has overload and short-circuit protection functions, it is not easy to achieve high reliability due to its complex structure. Products with poor quality are also prone to tripping, sliding buckle and other faults, which directly become ATSE faults. 2.5 since selective protection is a difficult problem, poor consistency of circuit breakers or improper calculation of selective protection are easy to cause the upper and lower circuit breakers to trip at the same time. If the circuit breaker of CB level ATSE trips at the same time with the lower circuit breaker, it will cause the power supply of important loads of other lines to be interrupted, and ATSE will lose its role in ensuring the power supply of important loads. 2.6 there are natural defects in the structure, which makes it difficult to achieve high reliability. ATSE composed of circuit breakers adopts motor + reducer drive. Every time the switch is switched, the motor must be "locked", and the reduction gear bears extreme pressure, resulting in short service life and low reliability of the motor and reducer. Coupled with the reliability of the circuit breaker itself, it is very difficult to achieve high reliability by using CB level ATSE composed of circuit breakers. This is the reason why world-famous ATSE manufacturers (such as ASCO, Ge, sokomi, Takata, Aichi, etc.) only manufacture PC level ATSE and give priority to PC level ATSE for important electric fields (such as airports, Olympic venues, subways, radio stations, communications, hospitals, etc.). 2.7 operation problems. General users (usually electricians) have been very familiar with the operation of circuit breakers, but they rarely know how to restore the ATSE function of ATSE composed of circuit breakers after the circuit breaker trips, which requires the latest scandal of Mitsubishi materials and Kobe Steel fraud, such as a special tool and operation method. Usually, there is no instruction manual on site, and it often needs the after-sales technical support personnel of the manufacturer to guide the electrician on site. Lead to long-term power failure of important loads. 2.8 maintenance problems. If the circuit breaker fails, the general electrician knows how to replace it (usually purchasing a circuit breaker with the same current level). However, when a circuit breaker of CB ATSE fails, electricians cannot replace it and must replace it with a new ATSE

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