When choosing the self-recovery fuse, we all want to know whether the starting protection speed of the self-recovery fuse is timely enough to protect the circuit equipment when the fault current occurs in the circuit.
There are many models of self-recovery fuse, and the starting protection speed of different models is different. Moreover, it takes different time for the same model to start protection under different fault currents.
When discussing the starting time of self-recovery fuse, only a rough range can be given. Unless a specific model is specified, a relatively accurate time value can be given in the corresponding current value. The protection action reaction time of plug-in self-recovery fuse is longer than that of sticking fuse.
If it is necessary to give the time range for self-recovery fuse to start protection? The premise is that the current twice the normal current is defined as the inimum fault current for starting protection, and when the normal current value is twice. All plug-in self-recovery fuses start protection within the time range of 0.1s~100s. Why is there such a large scope? Different models have different starting times.
The starting time of protection is regular. First, it is inversely proportional to the size of components. Second, it is inversely proportional to the fault current.
Is inversely proportional to the size of components, that is, in the same series, such as plug-in fuses of 250V series, the smaller the current, the smaller the components, twice the normal current, and the faster the start-up protection time due to its small size and fast heating.
Is inversely proportional to the size of the fault current, which is easy to understand, that is, the greater the fault current, the faster the heating of the device and the faster the protection. For example, when the fault current is 3 or 4 times of the normal working current, the protection time of many models can be started within 1 second.
