Correctly choose and install metal oxide arresters
1. Metal oxide arresters and arrester manufacturers in 10kV distribution network
The main function of a lightning arrester is to protect electrical equipment from insulation damage caused by lightning intrusion wave overvoltage and operating overvoltage.
2. Matters needing attention during installation, use and maintenance
(1) The nameplate should be checked before installation, and the system rated voltage of the arrester should be consistent with the system voltage of the installation point;
(2) The arrester is fixed on the bracket, its upper terminal is connected to the high-voltage line, and the lower terminal must be able to be grounded;
(3) The arrester cannot be used as a load-bearing support insulator and should be installed as close as possible to the protected equipment to reduce the impact of distance on the protection effect;
(4) The terminal arrester should be installed after the drop-out fuse to protect it when it is opened. A low-voltage arrester should be installed on the low-voltage side of the transformer to prevent overvoltage caused by forward and reverse conversion from damaging the transformer;
(5) When using lightning arresters and cold-shrinkable cable terminals, attention should be paid to the ambient temperature of the place of use. Metal oxide arresters are not suitable for installation in places with vibration or severe pollution and places with severe corrosive gases;
(6) Preventive tests should be conducted before the synthetic metal oxide arrester is put into operation and every two years after operation;
(7) The metal oxide arrester is sealed with a brass double-layer bottom cover. After being put into operation, preventive tests should be conducted every 5 years. When measuring the leakage current, a 10kV DC voltage should be applied to both sides of the arrester (AC pulsation is not greater than ±1.5%). The leakage current is required to comply with the specified value of the product;
(8) The grounding of the arrester should comply with the requirements of grounding regulations and European-style cable connectors.
3. Issues that should be paid attention to when selecting arresters
First of all, when choosing, you should pay attention to the place of use. Different places have different types of arresters.
Distribution type: To protect switch cabinets, transformers, box-type transformers, cable heads and other related distribution equipment of corresponding voltage levels from atmospheric and operating overvoltage damage, "HY5WS" metal oxide arresters should be selected.
Power station type: protects AC electrical equipment in power plants and substations from atmospheric overvoltage and operating overvoltage. You can choose "HY5WZ" or "Y5WZ" type;
Motor type: Limit the over-voltage generated when the vacuum circuit breaker or low-oil circuit breaker switches on the rotating motor, and protect the rotating motor from damage due to operating over-voltage. You can choose the "HY2.5WD" or "Y2.5WD" type;
Capacitor type: Suppresses the overvoltage generated by the capacitor bank when operating a vacuum circuit breaker or oil-less circuit breaker, and protects the capacitor bank from damage due to operating overvoltage. "HY5WR" type is optional.
In short, when using lightning arresters, you should choose products from regular manufacturers, carefully understand their performance and uses, and install them strictly in accordance with the requirements of relevant electrical installation regulations. 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
