What are HRC fuses?

 HRC fuses are High Rupturing Capacity fuses. Older types of fuses used a simple wire which would melt and even burn off when a certain level of current is exceeded. That is how we used to have blown fuses in the yester years. The body catridge of HRC fuse is made of heat resistant material like ceramic and there are two metallic end caps which connect to the circuit in the fuse holder. The current carrying element within the fuse is made of silver and the internal space of the fuse body is filled with a powder which prevents overheating and allows the fuse to carry normal rated current. Beyond the rated current, the silver element vaporizes and breaks the circuit. Chemical reaction between silver and the filling powder produces a high-resistance substance which helps to quench the arc in the fuse. 

 


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