A circuit breaker is a resettable overcurrent protection device. The symbol shows a line with a small rectangular notch or break. Unlike fuses, circuit breakers can be reset after tripping and are standard in residential electrical panels.
A fuse is a one-time overcurrent protection device. The symbol shows a small S-curve or thin line inside a rectangular enclosure. When current exceeds the rated value, the fuse element melts and breaks the circuit.
The ground symbol indicates a connection to earth or a common reference point. The symbol shows three progressively shorter horizontal lines stacked vertically. Proper grounding protects against electric shock and provides a reference voltage.
A surge protector clamps excessive voltage spikes to protect sensitive equipment. The symbol resembles a varistor or TVS diode with voltage-clamping indicators. Surge protectors are essential for computers, electronics, and industrial equipment.
