What issues should consumers pay attention to when purchasing lightning arrester manufacturers?
1. Overall dimensions of arrester
The insulation strength of the porcelain sleeve of the lightning arrester is determined according to the conditions of indoor and outdoor use, and its overall dimensions are related to the material of the valve plate. When it is used in overhead lines or outdoor power transformation and distribution equipment, due to its large phase spacing, the overall size of the arrester will not have any adverse effects. Due to its small size, indoor handcart-type switch cabinets will have adverse effects if the arrester size is large. The unit flow capacity of the SiC valve plate of the silicon carbide arrester is only 1/4 of the ZnO valve plate. Under the same flow capacity (5kA) condition, the diameter of the SiC valve plate is larger, and the outer diameter of the arrester is also larger; under the same rated voltage and residual voltage conditions, the height of the silicon carbide arrester is larger than that of the zinc oxide arrester. Especially the 35kV level is more significant. For example, the 112 plan of the JYN1-35 handcart cabinet originally used the FYZ1-35 gapless zinc oxide arrester with a height of only 650mm. It was installed on a simple handcart in the rear compartment of the cabinet with an isolation plug on the top. Since this product has been discontinued, the engineering design insisted on using the FZ3-35 silicon carbide arrester with a height of 1500mm. , the compartment height is not enough, so the busbar room and compartment partitions have to be cancelled, and the arrester is directly connected to the main busbar. In this way, the test or replacement of the arrester must be carried out when the entire main busbar is powered off, which makes operation and maintenance difficult. The outer diameter of the arrester is large and the air clearance between phases is not enough. The additional interphase insulation partitions have the potential for aging and moisture insulation accidents. The outer diameter and height of zinc oxide arresters are relatively small, and the 35kV level can also be made into a suspended type, such as the Y5CZz-42/110L series gap zinc oxide arrester, which is only 640mm in height. Miniature arresters are more convenient for installation and use in handcart cabinets.
2. Performance-price ratio of arrester manufacturers
The valve plate of the gapless zinc oxide arrester withstands the grid voltage for medium and long-term operation, and the working conditions are harsh. The valve plate must be strictly tested and screened during product manufacturing. The pass rate is low and the price is high. Because it has a fatal weakness of poor transient overvoltage tolerance, it is not suitable for promotion and use in my country's 3-35kV power grid. Because of the gap, the series gap zinc oxide arrester greatly improves the long-term working conditions of the valve plate. The test and screening requirements for the valve plate during product manufacturing are relatively low. The pass rate is high, the cost is low, and the price is cheaper. The price of the series gap zinc oxide arrester is more common than that of the gapless zinc oxide arrester. It is cheap, sometimes cheaper than silicon carbide arresters (such as 3-10kV FZ type). At the same time, it can enhance the strengths and avoid weaknesses of other lightning protection devices. It is actually the most advanced lightning protection appliance in the world. It has a high performance-price ratio and is a popular and popular product for the replacement of lightning arresters.
3. Issues with service life of arrester manufacturers
The service life of the arrester is related to many factors. In addition to manufacturing quality, seal failure, moisture and other external factors, the aging speed of the arrester valve is a key factor affecting the service life. Due to its heavy operation and load, large freewheeling current, and poor stability in operating characteristics, silicon carbide arresters may suffer from transient overvoltage hazards and other reasons, accelerate the aging of the valve plate, and have a short lifespan, generally 7 to 10 years, and even only 3 to 5 years. The valve plate of the gapless zinc oxide arrester has been subjected to the grid voltage for a long time. The working conditions are harsh, the inflection point voltage is low, and the frequency of action is high. It may also suffer from transient overvoltage hazards, temperature and thermal damage, etc., which rapidly accelerates the aging of the valve plate and has a shorter service life. Some are even shorter than silicon carbide arresters. The gap of the series gap zinc oxide arrester can ensure that the valve plate only withstands high voltage during the overvoltage protection action process, and the time is very short (within 100 μs). In other cases, the valve plate is either in an isolation state (pure gap) or in a low potential state (composite gap resistor voltage division) with respect to the grid voltage. This greatly improves the long-term working conditions of the valve plate. It is also protected from transient overvoltage hazards and temperature thermal damage, and ensures that the valve plate temperature does not exceed 55°C, thereby ensuring that the arrester life span is more than 20 years.
Yichang Hengyuan Technology Co., Ltd. specializes in the production of European-style cable joints, plug-and-pull heads, cable branch boxes, American-style elbow joints, high-voltage vacuum circuit breakers, high-voltage load switches, arresters, zinc oxide arresters, tank arresters, over-voltage protectors, counters, monitors, heat-shrinkable cable accessories, Manufacturer of cold shrink cable accessories, T-heads, wall bushings, European cable accessories, American cable joints, transformer neutral point protection devices, fuses, isolating switches, PT cable heads, elbow cable joints, 10kV outdoor terminals, switch cabinets, cable intermediate joints, cable accessories and other products
