Circuit breakers are switches that can remove electrical power from a circuit. They are designed to open automatically if the electrical current passing through them exceeds their ratings. For example, in a typical household circuit, there can be circuit breakers rated at 15 or 20 amperes, also called amps. In this way, circuit breakers protect household appliances from having excessive current, which can damage them. Excessive current can also cause overheating of wires and electrical devices, which can result in fires.
One of the main reasons for circuit breaker failure is lubrication. Circuit breakers have physical movements when they open, and the manufacturer typically lubricates the moving parts so that they can function correctly. However, in some environments, the lubrication can become ineffective over time. Other causes of circuit breaker failure are faulty breaker components, corrosion, dirt and debris, out of tolerance parts and material defects.
Circuit breaker failure is significant because they are considered safety devices. The failure of circuit breakers can cause fires because of the heating caused by excess current. Because of this, high-quality circuit breakers should be considered for use and they should be operated in an environment not open to dirt and debris. Most circuit breakers are kept from exposure to the environment by placing them in a circuit breaker box.
Circuit breakers should be inspected periodically to ensure that there is no dirt or debris buildup. They should also be checked for signs of corrosion, especially in humid climates. At any sign of corrosion, the circuit breaker should be replaced.
Some people believe that simply resetting a circuit breaker will solve the problem of the circuit breaker opening, which removes electricity from its associated circuit. It's important to understand that there is something on the circuit that is drawing excessive current. This might occur only intermittently. Monitor devices on the circuit to check for devices that might be overheating from the excessive current draw.
There is a high alternating current (AC) voltage present in circuit breaker boxes. Extreme caution should be used whenever working with live voltage. Although a circuit breaker can remove electricity from its circuit, there is still voltage present in the circuit box.