Automatic recloser is a circuit breaker with automatic reclosing function, which is generally used in outdoor lines, which can quickly recover transient faults and isolate permanent faults.
The sectionalizer is a load switch with the function of isolating the fracture. It does not have the ability to open and close short-circuit current. It can open and close rated current and close short-circuit current. Generally, it cooperates with the recloser and configures the corresponding controller, which can realize the line fault location and isolate the fault section. In contrast, the price of sectionalizers is much lower than that of circuit breakers and reclosers.
There is also a concept called a demarcation switch, which is actually the same concept as a segmenter or a segment switch, and the functions on the line are the same. The difference is: the demarcation switch is a circuit breaker, and the sectional switch is a load switch.
(1) Different functions: The function of the recloser vacuum circuit breaker is to cooperate with other high-voltage electrical appliances to identify the location of the fault through its circuit breaking, reclosing operation sequence, reset and blocking, so as to minimize the limit of the power outage area, while the circuit breaker is only used to break short-circuit faults, and the line blackout area is large.
(2) Different structures: The structure of the recloser is composed of an arc extinguishing chamber, an operating mechanism and a control system, and a vacuum circuit breaker is usually only composed of an arc extinguishing chamber and an operating mechanism. The operating mechanism of the domestic advanced recloser is a permanent magnet mechanism, and the operating mechanism of the circuit breaker is generally a spring mechanism. Compared with the spring mechanism, the permanent magnet mechanism has much fewer parts, maintenance-free and high reliability.
(3) Different control methods: The recloser has control equipment, and the detection, control, and operation form a self-contained system, while the circuit breaker and its control system are considered separately in design.
(4) Different breaking characteristics: The breaking of the recloser has inverse time characteristics and dual time. The circuit breaker commonly used quick-break and over-current protection.
(5) The operation sequence is different: the number of operations of the recloser is "four points and three closes", and there are "two fast, two slow", "one fast and three slow" according to the different places of use and the front and rear matching switch equipment. The rated operation order is: points— 0.1S—combination—1S—combination—1S—combination, the characteristics are easy to adjust; the operation sequence of the circuit breaker is uniformly stipulated by the standard: sub—0.3s—combination—180s—combination, the operation sequence is not adjustable, and it is the same as before and after. The switchgear does not cooperate.
A circuit breaker is a switching device capable of closing, carrying and breaking current under normal or abnormal circuit conditions. Vacuum circuit breakers can be used to distribute electric energy, start asynchronous motors infrequently, and protect power lines and motors. Circuit breakers are divided into high-voltage circuit breakers and low-voltage circuit breakers according to their scope of use. The above are called high-voltage electrical appliances.