What Is a Power Breaker?
A power breaker, commonly referred to simply as a breaker, is an essential component in electrical systems. It is used to connect power lines to electrical machinery, typically through a power distribution or control panel. The connection from the breaker to the machinery is often made using components like electromagnetic contactors.
Power breakers are vital not only in industrial settings but also in residential environments.
Uses of Power Breakers
Power breakers are crucial for protecting equipment and preventing fires by interrupting the power supply in cases of overcurrent. This function is essential when connecting devices like plugs or operating power-driven machinery.
There are two main types of power breakers: wiring breakers and leakage breakers. Wiring breakers, also known as safety breakers, cut off the power supply when the current exceeds a set limit. Leakage breakers perform a similar function but also detect and interrupt power leakage from equipment or wiring.
Principle of Power Breakers
The capacity of a breaker is indicated by its Ampere Frame (AF), which also determines the size and interrupting capacity. The rated current is represented by Ampere Trip (AT), denoting the current level at which the breaker will trip. AF indicates the maximum current a breaker can handle, while AT specifies the tripping threshold.
Breakers can trip based on three different mechanisms. The first is thermal-magnetic, utilizing a bimetal strip that bends when heated by overcurrent, triggering a trip. The second is electromagnetic, where an electromagnetic force generated by overcurrent overcomes a spring, causing the breaker to trip. The third type is electronic, employing circuitry to detect overcurrent and activate the tripping mechanism.