The load switch is a split switch with a dedicated arc extinguishing contact, an arc extinguishing device and a spring disconnecting device. Structurally, the load switch is similar to the disconnector (has a visible break point in the open state), but it can be used to open and close the circuit, which is similar to the circuit breaker. However, the circuit breaker can control any circuit, and the load switch can only open and close the load current, or cut off the load current, so only for cutting and switching under normal circumstances, and can not be used to disconnect the short-circuit fault current. However, it is required that its structure be able to pass fault current at short circuit time without damage.
The advantages of the load break switch is the lower price, and more for 10 kV or less of the distribution line, the arc method of air, compressed air, SF6 and vacuum arc and so on several. With the continuous development of science and technology, the type and quality of load switches have increased and improved.The load switch has a simple arc extinguishing device, its arc suppression capacity is limited, in the circuit normal work, used to turn on or off the load current, but when the circuit is broken, can not be used to cut off the huge short-circuit current, load switch off , There are visible break points, is its characteristics.
Isolation switch does not have a special arc extinguishing device, the arc ability is weak, it is generally used to isolate the voltage, will have been cut off by the short circuit, no load current flowing through the circuit connected or cut off, and can not be used to turn on or cut off the load Current. The main purpose of the disconnector is when the electrical equipment to be power outage maintenance, use it to isolate the power supply voltage, and cause a clear disconnect point to ensure the safety of maintenance personnel.
The load switch is a split switch with a dedicated arcing contact, an arc extinguishing device and a spring disconnecting device. Structurally, the load switch is similar to the disconnector (which has a visible break point in the open state), but it can be used to open and close the circuit, which is similar to the circuit breaker. However, the circuit breaker can control any circuit, and the load switch can only open and close the load current, or cut off the load current, so only for cutting and switching under normal circumstances, and can not be used to disconnect the short circuit fault current. However, it is required that its structure be able to pass through the short-circuit fault current without damage. Since the extinguishing device and the contact of the load switch are designed to be cut and connected to the load current, the load switch should, in most cases, be used in conjunction with a high voltage fuse, which serves as a task for cutting off the short circuit fault current. load break switch opening and closing frequency and operating life is often higher than the circuit breaker.
