In an e-mail I sent several days ago, I mentioned the three ratings of a fuse or circuit breaker: the normal current, the voltage, and the interrupting rating In that e-mail I specifically talked about the voltage rating and why it’s a "not to exceed rating". I also recently discussed the differences between short circuits and overloads (yes...the knowledge base is growing...and no...this won’t be on the final exam...)
Now I’d like to talk briefly about the "interrupting rating" of a fuse or circuit breaker.
Short-circuits create excessively high currents and heat, which can be potentially explosive and very dangerous to people and equipment. In a short-circuit there can be as much as 1000 times the normal current (for example...if the circuit current is normally 10A...a short-circuit could be as high as 10,000 amps!!).
The interrupting rating of any over-current device is the ability of that device to safely open the circuit at the rated voltage. In practical terms, this means that the short-circuit should not cause the fuse or circuit breaker to explode or catch on fire when opening a short-circuit. Every fuse or circuit breaker intended to open a short-circuit has an interrupting rating and it should never be exceeded*.
Thank you so much for your continued support of OptiFuse....please pardon our daily interruption as we try to educate and motivate...