Circuit breaker is a common protection device in electrical systems. It can effectively protect circuits and equipment from overload, short circuit and other faults. It is an essential part of electrical work. This article will introduce seven circuit breaker knowledge points that electricians must know to help electricians better understand and apply circuit breakers to ensure the safe operation of circuits and equipment.
1. The function and principle of circuit breaker
function: The circuit breaker is mainly used to cut off the circuit, protect the circuit and equipment, and prevent damage caused by overload, short circuit and other faults.
Principle: The circuit breaker judges whether to cut off the circuit by detecting the current size and time in the circuit, and protects the safe operation of the circuit and equipment.
2. Types and classification of circuit breakers
type: Circuit breakers can be divided into thermal release circuit breakers, magnetic power circuit breakers, leakage circuit breakers and other types according to their use and working principle.
Classification: Circuit breaker according to the voltage level can be divided into low voltage circuit breaker, medium voltage circuit breaker, high voltage circuit breaker; according to the use can be divided into air circuit breaker, vacuum circuit breaker, SF6 circuit breaker and so on.
3. Rated current and rated short-circuit capacity of circuit breaker
rated current: the maximum current value that the circuit breaker can work normally, usually marked on the circuit breaker, electricians should pay attention to matching the rated current value when selecting and installing the circuit breaker.
Rated short-circuit capacity: The maximum short-circuit current that the circuit breaker can withstand, and the circuit breaker can cut off the current within a certain period of time without damaging itself.
4. Selection and installation of circuit breakers
selection: the electrician in the choice of circuit breaker to consider the load characteristics of the circuit, rated current and rated short-circuit capacity and other factors, select the appropriate circuit breaker model.
Installation: The installation position of the circuit breaker should be reasonably selected. It is required to be fastened firmly and wired correctly to ensure that the circuit breaker can work normally.
5. Protection function of circuit breaker
overload protection: When the circuit load exceeds the rated value, the circuit breaker will automatically cut off the current to prevent the equipment from overheating or damage.
Short circuit protection: in the event of a short circuit, the circuit breaker can quickly cut off the current, to avoid the expansion of the circuit fault.
6. Maintenance and fault handling of circuit breaker
maintenance: Regularly check the working status and wiring of the circuit breaker to ensure the normal operation of the circuit breaker; clean the surface and ventilation holes of the circuit breaker to prevent dust accumulation from affecting the work.
Troubleshooting: When circuit Breaker in case of tripping, failure to reset and other faults, the electrician shall timely investigate the cause of the fault and repair or replace the fault circuit breaker.
7. Application scope and precautions of circuit breaker
applications: Circuit breakers are widely used in circuit protection and control in residential, commercial, industrial and other fields, and are indispensable and important devices in electrical systems.
Note: Electricians should pay attention to safe operation when using circuit breakers, abide by relevant regulations, and avoid damage to circuits and equipment caused by operational errors.
