What are the functions of high voltage load break switch
The high-voltage load break switch/ LBS is a combined high-voltage electrical appliance, which consists of an isolating switch, a fuse, a thermal relay, a shunt release and an arc extinguishing device.
The high-voltage load switch has a simple arc extinguishing device, which can only be used to make and break the normal load current, and cannot be used to break the short-circuit current.
Therefore, the high-voltage load switch is often matched with a high-voltage fuse and a thermal release, and the fuse is used to cut off the short-circuit current during a short circuit. When the load is overloaded, the thermal release acts to automatically trip the load switch.
Since there is an obvious gap when the load switch is disconnected, it also has the function of isolating the power supply to ensure safe maintenance.
High-voltage load switch and combined electrical appliances are suitable for three-phase AC 10 kV, 50 Hz power system, or used in conjunction with complete sets of power distribution equipment, ring network switch cabinets, combined substations, etc., and are widely used in area network construction and renovation projects , industrial and mining enterprises, high-rise buildings and public facilities, etc., can be used as a ring network power supply or terminal, and play the role of power distribution, control and protection.
It has the advantages of large breaking capacity, safety and reliability, long electrical life, frequent operation, compact structure, small size, light weight, and basically no maintenance. With breaking rated current, overload current. It can break short-circuit current and prevent the operation of equipment from lack of phase. The switch has an obvious isolation fracture. It is equipped with an electric spring mechanism of the grounding switch with closing ability, which can be remotely controlled.
According to the arc extinguishing medium, the high-voltage load switch is mainly divided into gas production type, compressed gas type, vacuum type and SF6 type. According to the installation location, it is divided into two categories: indoor type and outdoor type.
The load break switch is simple in structure, small in size and low in price, and is suitable for occasions that require no oil, no maintenance, and frequent operations. In combination with fuses, it can be used as a power switch for users with small or unimportant capacity to replace circuit breakers. The load switch is selected according to the rated voltage and rated current, and is checked for pressing and thermal stability. When equipped with a fuse, the breaking capacity of the fuse should be verified, and its dynamic and thermal stability may not be verified.
