Year1
- 型号：
- HH10-15/3
- 电流：
- 15A
- 种类：
- 铁壳开关
The official name of low-voltage enclosed load iron shell switch is enclosed load switch or fuse type load switch. It is a casing made of steel plate or cast iron, equipped with a fuse for cutting off short-circuit current, a knife switch for connecting and breaking the circuit, and an operating mechanism for operating the knife switch. It can therefore be manually operated for infrequent making and breaking of circuits and for short-circuit protection. It is widely used in electrical installations in industrial and mining enterprises, electric heating lighting and rural power drainage and irrigation, and can be used for infrequent direct starting and stopping of small induction motors.
The low-voltage iron shell enclosed load switch-/3 is a switch with a special arc-extinguishing contact, arc-extinguishing device and spring circuit breaker. From a structural point of view, the load iron case switch is similar to the isolating switch (it has a visible disconnection point in the off state), but it can be used to open and close circuits, which is similar to a circuit breaker.
However, the circuit breaker can control any circuit, while the low-voltage iron-shell enclosed load switch-/3 can only switch the load current, or break the overload current, so it is only used to cut off and connect the circuit under normal circumstances. , and cannot be used to interrupt short-circuit fault current. However, its structure is required to be able to pass the fault current during the short circuit time without being damaged. Since the arc extinguishing device and contacts of the low-voltage iron-shell enclosed load switch-/3 are designed to cut off and connect the load current, the iron-shell load switch should be used in conjunction with a high-voltage fuse in most cases, and the latter To take on the task of cutting off short circuit fault current. The opening and closing frequency and operating life of the low-voltage iron-shell enclosed load switch-/3 are often higher than that of the circuit breaker.
The advantage of the low-voltage iron-shell enclosed load switch-/3 is that it is relatively low-priced and is mostly used in distribution lines below kilovolts. Its arc extinguishing methods include air, compressed air, and vacuum arc extinguishing. With the continuous development of science and technology, the types and quality of load iron case switches have increased and improved.
The low-voltage iron-shell enclosed load switch-/3 has a simple arc extinguishing device with limited arc extinguishing ability. It can be used to connect or cut off the load current when the circuit is working normally, but it cannot be used when the circuit is open. To cut off the huge short-circuit current, the low-voltage iron-shell enclosed load switch-/3 has a visible disconnect point after disconnection, which is its characteristic.
The plastic-covered knife switches and iron-cased switches used before the 1980s are both low-voltage load switches. For low-voltage load switches with small capacity of high-voltage fuses, the opening and closing speed of the contacts is related to the operating speed of the handle. The operating mechanism of the low-voltage load switch with a large capacity adopts the spring energy storage action principle. The opening and closing speed has nothing to do with the speed of the handle operation. The structure is relatively simple and is equipped with a reliable mechanical interlocking device. The switch cannot be closed or switched after the cover is opened. The cover cannot be opened after closing, ensuring work safety.
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