When a circuit is overloaded or short-circuited, the current in the circuit rises continuously, which may damage some important devices in the circuit, or may burn the circuit or even cause a fire. The role of the fuse is to protect the circuit by breaking itself when the circuit fails.

An explosion-proof fuse is a fuse that does not explode or burn on the basis of the fuse itself blowing to cut off the current. If an explosion-proof fuse is correctly placed in the circuit, the safety will be greatly improved.

Principle of operation

Fuses protect electronic equipment from overcurrents and from serious injury caused by internal malfunctions. For this reason, each fuse has a rating and will blow when the current exceeds the rating. A fuse should operate safely without endangering its surroundings when acted upon by a current between the normal non-blowing current and the rated breaking capacity specified in the relevant standard. The expected fault current of the circuit in which the fuse is placed must be less than the rated breaking capacity current specified in the standard; otherwise, when a fault occurs and the fuse blows, there will be continuous arcing, ignition, blowing of the fuse, melting of the fuse together with the contacts, and the fuse marking will not be recognizable.

Of course, the breaking capacity of poor-quality fuses does not meet the requirements of the standard, the use of the same will be harmful. Explosion-proof fuse breaking capacity is much higher than the standard rated breaking capacity, filled with arc extinguishing agent, can effectively extinguish the arc in a timely manner to ensure the safe and reliable operation of the circuit.

Explosion-proof principle

General fuse by the electrode, support body, melt three parts, and explosion-proof fuse and arc extinguishing device, because this type of fuse to protect the circuit is not only a larger fault current, and when the melt melt its voltage is also higher at both ends, there will often be a melt has been melted (melting) or even vaporized, but the current is not cut off, the reason is that in the melting of the moment in the voltage and current under the action, the fuse has been melted. Arc phenomenon occurs between the two electrodes of the fuse. The arc extinguishing device must have a strong insulation and good heat absorption, and is negatively charged. Arc extinguishing equipment has a unique complementary arc extinguishing ability. One of the most important arc extinguishing agent, which includes a combination of SiO2 and chlorinated salts.

Because in the use of fuses, especially micro-fuses, when the fault current is too large or short-circuit disconnect instantly, which will produce a strong energy on the arc, the arc will produce an instantaneous high temperature, at this time it is necessary to extinguish the arc agent to extinguish the arc, arc extinguishing agent in the main role of SiO2 is to instantly absorb the heat of the arc, to avoid arcing of the ions produced by the arc because of the high temperature conditions are pulled arc, and the role of chlorinated salts, when the arc is generated When the arc is generated, the chlorinated salt will be decomposed due to the high temperature of the arc, and at the same time absorb the heat of the arc to further reduce its destructive effect, in addition, the chlorinated salt decomposition will produce chloride ions, chloride ions in the neutralization of the arc generated by the ions have a very good arc extinguishing effect.