company news about How to judge whether the circuit should use fuse or circuit breaker?

        The fuse and the circuit breaker have the same function, both of which are circuit protection appliances, mainly used to protect the overload and short circuit of the circuit.

        When the circuit is overloaded or short-circuited, both devices will open the circuit, and they usually work together. Fuses are generally more cost-effective than circuit breakers, but unlike circuit breakers that can be reset, fuses need to be replaced after fusing. The size of circuit breaker is usually 4-5 times of the equivalent fuse protection device.

        In general, the fuse is more suitable for faults with extremely high breaking current, so it is usually installed in front of the distribution board/distribution board or electrical equipment as backup protection. For example, the breaking capacity of the circuit breaker may be 5kA, and any fault current higher than this value will cause damage to the circuit breaker. In contrast, the breaking capacity of fuse can reach 20kA or even 50KA or higher, depending on its design.

        In addition, the fuse will not vaporize or explode under extreme fault conditions, so it will not damage the electrical system or equipment it protects. This means that in applications such as substations, fuses are usually used upstream of the distribution system.

        The fusing action speed of fuse can reach microseconds（ μ s) Class, that is to say, its speed is much faster than that of circuit breaker, and this ability is usually more suitable for installation and use in situations with similar requirements for fast cutoff. The tripping action speed of the circuit breaker is millisecond (ms), so it can be seen that it is much slower than the fuse, so it can only be used in situations where the cut-off speed requirement is not very high. Since each application is different, users should study carefully to determine the best overcurrent protection device.