the difference between load switch and circuit
load switch
the load switch is a switching appliance between the circuit breaker and the isolating switch. it has a simple arc extinguishing device and can cut off the rated load current and a certain overload current, but it cannot cut off the short-circuit current.
breaker
a circuit breaker refers to a switching device that can close, carry, and break current under normal circuit conditions and can close, carry, and break current under abnormal circuit conditions within a specified time. circuit breakers are divided into high-voltage circuit breakers and low-voltage circuit breakers according to their scope of use. the boundary between high and low voltage is relatively vague. generally, 3 kV the above are called high voltage electrical appliances.
the load switch can break normal operating current and short-circuit current. schneider's load switch cabinet SM6 it can break the normal working current about 200 times and the short-circuit current about 20 times. high-voltage circuit breakers can generally break normal current up to about 10,000 times, and can break short-circuit current dozens of times (usually 20 ～50second-rate). however, high-voltage circuit breakers are relatively expensive. today's load switches can be operated electrically, that is, they can be equipped with tripping and closing coils. therefore, circuit breakers are generally used in places that need to be disconnected frequently, and load switches are generally used in places that do not need to be disconnected frequently.
1、the load switch can be broken with load and has a self-extinguishing function, but its breaking capacity is very small and limited.
2、isolating switches generally cannot break loads. there are isolating switches that can break loads without an arc extinguishing cover. however, the structure is different from load switches and is relatively simple.
3、both load switches and isolating switches can form obvious disconnection points. most circuit breakers do not have an isolation function, and a few circuit breakers have an isolation function.
4、the isolation switch does not have a protection function. the protection of the load switch is generally a fuse protection, which only has quick-break and over-current protection.
5、the breaking capacity of circuit breakers can be made very high during the manufacturing process. mainly rely on adding current transformer secondary equipment for protection. it can have short circuit protection, overload protection, leakage protection and other functions.
