A circuit breaker is a device that can close, load and break the current under normal loop conditions, and can close, load and break the current under abnormal loop conditions (including short-circuit conditions) within a specified time. Circuit breakers can be used to distribute power, start asynchronous motors infrequently, protect power lines and motors, and automatically cut off circuits when they are seriously overloaded or short-circuited or under-voltage, its function is equivalent to the combination of fuse-type switch and over-underheat relay. In addition, it is not necessary to change the parts after breaking the fault current. At present, it has been widely used.
01
The function of circuit breaker
Cut off and connect the load circuit, as well as cut off the fault circuit, prevent the accident to expand, ensure safe operation. High-voltage circuit breaker to break 1500V, current of 1500-2000A arc, these arc can be stretched to 2m still continue to burn out. Therefore, arc extinguishing is a problem that must be solved in high voltage circuit breaker.
Low-voltage circuit breakers, also known as automatic air switches, can be used to switch on and off load circuits or to control motors that do not start frequently. Its function is equal to the total function of switch, over-current relay, loss-voltage relay, thermal relay and leakage protector, etc. .
Low-voltage circuit breaker has many protection functions (overload, short-circuit, under-voltage protection) , adjustable action value, high breaking ability, easy operation, safety and so on. Structure and working principle low voltage circuit breaker is composed of operating mechanism, contact, protective device (all kinds of release) , arc extinguishing system and so on.
02
The difference between circuit breaker and air switch
Air Switch:
a kind of switch that will trip if there is a short circuit. When the short-circuit or serious overload current occurs, the short-circuit current exceeds the set current value of the instantaneous trip, and the electromagnetic release produces enough suction to absorb the armature and hit the lever to make the hook rotate upward around the axle seat and release the lock, under the action of the reaction spring, the lock will break the three pairs of main contacts and cut off the power supply.
When the general overload occurs on the line, the overload current can not make the electromagnetic release act, but it can make the thermal element generate a certain amount of heat, make the bimetal sheet bend upward under the heat, push the lever to make the hook and the lock release, and break the main contact, cut the power. Because there are many ways of insulation, there are oil switches, vacuum switches and other inert gas (Sulfur hexafluoride gas) switch. Air Switch is the use of air arc switch, so called Air Switch. Air is used to extinguish the arc produced in the switching process. That’s why it’s called an air switch.
Circuit Breaker:
with over-current, short-circuit automatic release function, with degaussing arc extinguishing device, can be used to turn on and off the current; Air Switch: a circuit breaker, its arc extinguishing device exposed in the air, in the air medium environment can be completed to eliminate the arc, this type of electrical generally used in low-voltage circuit.
1. Voltage level difference: general air switch applicable to the voltage level of 500V below, and circuit breakers can usually be applied to more than 220V each voltage level.
2. The ability to block the current is different: the general circuit breaker can withstand the load and short-circuit current is greater.
3. ARC extinguishing medium and mode of distinction: Circuit Breaker arc extinguishing medium and mode not only air circuit breaker, but also vacuum circuit breaker, more oil circuit breaker, less oil circuit breaker, Sulfur hexafluoride circuit breaker and so on.
4. The difference of matching equipment: generally speaking, compared with the open circuit breaker measurement, logic and operating part of the organization supporting the equipment more complex.
For more information on circuit breaker, please feel free to call Slocable at 86-769-22010201. You can also email us at pv@slocable.com.cn.
