Fast fuse
The fast fuse is one kind of fuse, the fast fuse is mainly used in the short circuit protection. The overload capacity of semiconductor devices is very low. Can withstand large overload current in a very short period of time, thus requiring fast fuse circuit protection. The structure of the fast fuse is basically the same as that of the packing seal, but the melt material and the shape are different. It is a variable cross-section melt with V shaped deep groove.
Fast fuse fuse in addition to metal wire with a certain shape, will be in the above some material of solder joint, its purpose in order to make the fuse in overload situations quickly disconnected.
chinese name: Fast fuse 快速熔断器
Type: fuse
Use: short circuit protection
Structure: V shaped deep groove with variable cross section
2 the structure, working principle and characteristics of the fast fuse
After the rapid fuse structure
The arc after the rapid fuse principle
After the characteristics of fast fuse
The basic concept of
The fast fuse is one kind of fuse, the fast fuse is mainly used in the short circuit protection.
Fast fuse VICFUSE due to the overload capacity of semiconductor components is very low. Can withstand large overload current in a very short period of time, thus requiring fast fuse circuit protection. The structure of the fast fuse is basically the same as that of the packing seal, but the melt material and the shape are different. It is a variable cross-section melt with V shaped deep groove.
Fast fuse fuse in addition to metal wire with a certain shape, will be in the above some material of solder joint, its purpose in order to make the fuse in overload situations quickly disconnected.
Fast fuse will highlight the "fast", also has the advantages of high sensitivity, when the circuit current overload, fuse in the solder joints, rapid heating, rapid fault fuse, fast fuse and its efficiency is quite high, mainly used to protect thyristor and a number of electronic power components.
Structure, working principle and characteristics of fast fuse
Structure of fast fuse: fuse is composed of six parts: magnetic shell, conductive plate, melt, quartz sand, arc extinguishing agent and indicator. The melt is made of sterling silver, rectangular shaped sheet, and has a narrow neck hole.
Fast fuse arc quenching principle: fast fuse melt is made from sterling silver, due to the silver of the low resistivity, good ductility, chemical stability good, so fast fuse melt can make a chip and with a circular narrow neck structure. When a short circuit fault occurs, the current density of the narrow neck is large, so the narrow neck is first fuse, and the quartz sand is divided into a number of short segments. In this way, the arc is divided into many small segments, arc current is smaller, the distribution of the space is small, easy to be absorbed by the arc extinguishing agent. And because the quartz sand is insulated, the arc extinguishing immediately after the formation of an insulator, the circuit breaking.
Characteristics of fast fuse: anti time limit current protection. Fuse has the anti time delay characteristic, namely the overload current hour, the fuse time is long; the overload current is big, the fuse time is short. Therefore, in a certain overload current and overload time range, the fuse is not fuse, and can be used continuously. Fuse has a variety of fusing characteristic curve, it can be applied to different types of protection of the needs of the object.
Due to the melt of the fast fuse, the fuse is provided with a series of rectangular thin slices with a narrow neck. The narrow area at the neck of the round hole is small, the heat capacity is small, a short circuit fault occurs, the fault current has not reached the expected short circuit current, that is, the fuse is fused, and the arc is divided into a lot of small segments by quartz sand. In this way, the short circuit current is limited, and the arc extinguishing is accelerated.
Breaking capacity: a short circuit fault occurs, the narrow neck of the round hole is first fused, the arc is divided into many small pieces of quartz sand, the arc is quickly extinguished. Since the quartz sand is insulated, the fuse is immediately turned into an insulator after the arc is extinguished, and the circuit is broken off. So fast fuse breaking capacity is strong, can be as high as 50kA.
Load equipment to withstand the impact of small energy: short circuit fault occurs, the load equipment to withstand the impact of energy
W=I²Rt
W=I - Rt
I - short circuit current; R - circuit resistance; t - from short circuit fault occurs to the circuit to be cut off. The quick fuse has a short time, and has a very good current limiting function.