What are current limiting fuses and Class H fuses?
Not all fuses are current limiting; Class H fuses are not current limiting and are known as CODE fuses. A current limiting fuse is specifically designed to quickly interrupt the circuit during overcurrent situations.
Understanding Current Limiting Fuses:
A current limiting fuse is a type of fuse that is designed to not only break the circuit when the current exceeds the rating, but also to limit the duration and let-through energy of the fault current. When an overcurrent situation occurs, a current limiting fuse operates by quickly breaking the circuit and thereby stopping the flow of current to protect the circuit from damage.
Explaining Class H Fuses:
are a class of fuses that are not current limiting and were commonly used in residential and commercial installations in the past. While they are sometimes known as CODE fuses, it's important to note that Class H fuses are not current limiting. Unlike current limiting fuses, Class H fuses do not have the ability to quickly interrupt the circuit during overcurrent situations.
Importance of Understanding Fuses:
Current is defined as the flow of charge, which is measured in amperes (amps). This fundamental concept underlies the functionality of fuses and circuit breakers. When the current passing through a fuse wire exceeds its rated current, the wire heats up, melts, and interrupts the circuit. This safety mechanism protects circuits from excessive current that could lead to overheating, damage, or fire.
In certain applications where high current may be present for longer periods, special types of fuses like slow blow fuses are used. It's crucial to have a good understanding of the different types of fuses available and their specific roles to ensure the safety and protection of electrical circuits.