The industrial circuit breaker is an extremely critical mechanism within the electrical system mostly for the measure of safety that it provides. The reason is simple: whenever the electrical wiring in a structure (i.e. building, facility, home) has too much current flowing through it, the industrial circuit breaker cuts the power until someone can fix the problem. Without the existence of circuit breakers, household and facility electricity would be unusable because of the potential for fires and other potential electrical mishaps resulting from wiring problems and/or equipment failures.
To fully understand the function and therefore the industrial circuit breakers importance, it is first imperative that you first understand how electricity works. The concept of electricity is generally defined by three major characteristics:
- Voltage: the pressure that makes the electric charge move.
- Current: is the charge’s flow or the rate at which the charge moves through the conductor, measured at a specific point.
- Resistance: the conductor offers a particular amount of resistance to the flow of electricity, which varies depending on the conductor’s composition and size.
These three terms (voltage, current, and resistance) are interconnected. As a result, one cannot change or be altered without affecting the other. Think about it: if you increase it the pressure working on an electric charge or decrease the resistance, more charge will flow. If you decrease or increase resistance, less charge will flow.
The Industrial Circuit Breakers Basic Design
The simplest circuit protection device is the fuse. A fuse is a thin wire, enclosed in casing that plugs into the circuit. When a circuit is closed, all charge flows through the fuse wire, and the fuse undergoes the same current as any other point along the circuit. In addition, the fuse is designed to disintegrate when it heats up above a certain temperature, thereby burning the wire. Destroying the fuse opens the circuit before the excess current can damage the building wire. However, the problem with fuses is that they only work once. Every time a fuse is blown, you have to replace it with a new one. An industrial circuit breaker does the same thing as a fuse – it opens a circuit as soon as a current climbs to unsafe level – but the advantage over a simple fuse is that an industrial circuit breaker can be used over and over again.
The basic industrial circuit breaker consists of a simple switch, connected to either a bimetallic strip or an electromagnet. The hot wire in the circuit connects to the two ends of the switch. When the switch is flipped to the ON position, electricity can flow from the bottom terminal, through the electromagnet, up to the moving contact, across the stationary contact and out to the upper terminal.
The electricity magnetizes the electromagnet thereby increasing current boost, which increases the electromagnet’s magnetic force, and decreasing current lowers the magnetism. When the current jumps to unsafe levels, the electromagnet is strong enough to pull down a metal lever connected to a switch linkage. The entire linkage shifts, tilting the moving contact away from the stationary contact to break the circuit. The result: the electricity shuts off.