Headaches can lead to scalp pain and to pain in any area of the face, neck or head. Several types of headaches may cause scalp pain, such as migraine, sinus headache, tension headache, and those caused by nerve involvement such as occipital neuralgia.
The circuit breaker. The circuit breaker does the same job as the fuse, but works in a different way. A spring-loaded push switch is held in the closed position by a spring-loaded soft iron bolt. An electromagnet is arranged so that it can pull the bolt away from the switch.
The circuit breaker must detect a fault condition; in low voltage circuit breakers this is usually done within the breaker enclosure. Circuit breakers for large currents or high voltages are usually arranged with protective relay pilot devices to sense a fault condition and to operate the trip opening mechanism. Also indicates the status of the circuit breaker (On or Off/tripped). 2  Most breakers are designed so they can still trip even if the lever is held or locked in the on position. 3  This is sometimes referred to as free trip or positive trip operation. 4  Actuator mechanism-forces the contacts together or apart.