When the system software fails, the common fault components protect the posture, and the circuit breaker actually operates the common fault to reject the trip, the adjacent circuit breaker of the substation will protect the trip according to the common fault components. If the conditions do not allow, the safety channel can also be used to make the remote circuit breaker trip at the same time. The wiring method is called circuit breaker common fault protection.
Generally speaking, after the movement of the phase current components, 2 groups of running connectors are derived and connected in series with the external posture protection connectors, and then the common fault protection is run on the route.
What does a circuit breaker do?
Circuit breakers are mainly used in motors, large space transformers and distribution stations that often disconnect loads. The circuit breaker has the function of breaking the safety accident load, and cooperates with various relay protections to protect electrical equipment or routes.
The circuit breaker is generally used for part of the low-voltage lighting driving force, and can automatically disconnect the circuit; the circuit breaker also has several functions such as load and short-circuit fault protection, but once there is a problem with the load below, it must be maintained. function, and the breakdown voltage of the circuit breaker is insufficient.
Today there is a functional circuit breaker with protection, which combines the functions of a general circuit breaker and a high-voltage disconnector. The functional circuit breaker with protection can also be used as a human body high-voltage isolation switch. In fact, high-voltage isolating switches generally cannot be operated with load, but circuit breakers have protection functions such as short-circuit fault, load protection, and under-voltage protection.
Describes the working principle of circuit breakers in detail
Basic Type: A simple circuit protection device is a fuse. A fuse is just a thin cable, with a protective sheath, that is then connected to the circuit. After the circuit is turned off, all current must pass through the fuse, and the current of the fuse is the same as the current of other points on the same circuit. This type of fuse is designed to remain open when the ambient temperature reaches a certain level. Damaged fuses can also lead to lead paths to prevent excess current from damaging house wiring. The problem with the fuse is that it only has one effect. Every time the fuse is damaged, it must be replaced with a new one. A circuit breaker can perform the same function as a fuse, but can be reused many times. As long as the current reaches a risky level, it will immediately lead the way.
Basic principle: The live wire and neutral wire in the circuit are connected to both sides of the power switch. When the button is in the connected state, the current is discharged from the bottom terminal equipment, successively flowing through the electromagnet, the moving AC contactor, the static data AC contactor, and finally discharged from the top terminal equipment. Electric current can be magnetized electromagnet. The magnetic force produced by the electromagnet increases with the current. If the current is reduced, the magnetic force will also weaken. When the current jumps to the risky capacity, the electromagnetic induction sense creates a magnetic force strong enough to move the metal rod connected to the power switch linkage. This will cause the mobile AC contactor to skew and leave the static data AC contactor, opening the circuit. The current is also interrupted. Wear-resistant steel strips are designed according to the same principle. Unlike English, it doesn’t need to give the electromagnet kinetic energy, but instead allows the metal strip to bend under a high current, which then runs the linkage. Some circuit breakers move the power switch according to the charge of explosives. When the current exceeds a certain level, it will ignite flammable and explosive raw materials, and then push the piston rod to press the switch
Enhanced: The more advanced circuit breakers choose to abandon simple electrical equipment and use electronics (semiconductor industry) to detect current levels. Ground Fault Interrupter (GFCI) This is a new type of circuit breaker. These circuit breakers not only prevent damage to house wiring, but also protect people from electrocution.
Enhanced principle: The GFCI will continue to detect the current in the neutral and live wires in the circuit. When all is well, the currents in the two circuits should be exactly the same. Once the live neutral is grounded immediately (for example, some people accidentally touch the live neutral), the current in the live neutral will suddenly surge, but the neutral will not. When the GFCI detects such a thing, it immediately disconnects the circuit to prevent electrocution. GFCIs do not have to wait until the current rises to risky levels, so their response rate is much faster than conventional circuit breakers.
Post time: Aug-04-2022