Electrical Safety Devices
Electricity makes the world run by powering computers and buildings, recharging batteries for portable handheld devices and keeping our buildings warm. However, electricity is also dangerous to humans and equipment, so electrical safety devices have been designed as protection against potential electrical hazards.
Electrical Safety Devices – Circuit Breakers
Electrical safety devices protect electrical circuits from short circuits or overloads. A circuit breaker is designed to stop incoming electrical flow at the sign of any irregularities (faults) such as an overload (more than normal electrical flow that the electrical system can handle). Once triggered, circuit breakers can be automatically or manually reset, unlike fuses that have to be replaced once used. Circuit breakers vary in size to protect electrical equipment from small (fit for a home) to large (fit for a city).
Electrical Safety Devices – Fuses
Fuses are electrical safety devices that are considered sacrificial lambs. A fuse is a simple metal strip or wire that melts when it’s exposed to high levels of electricity. This happens when too much electricity flows into the power system. The fuse interrupts the connected circuit and absorbs the electrical overflow to protect electrical equipment from extensive damage caused by fire or overheating. Fuses, among other overcurrent protection devices, are required in electrical systems to protect human life and to avoid property damage.
Electrical Safety Devices – Ground Fault Circuit Interrupters (GFCIs)
Ground Fault Circuit Interrupters are electrical safety devices that are designed to limit the damage of electrical shocks by quickly disconnecting the circuit when the return neutral conductor and the energized conductor are not balanced. This electrical safety wiring device disconnects the circuit wherever this imbalance is located. Imbalances can be caused by current leaks through human tissue due to accidental grounded contact with energized circuits. This electrical safety device can be effective under these conditions, however, provide limited protection against short-circuits or overloads.
Electrical Safety Devices – Protective Relays
Protective relays evaluate the ongoing operation of electrical circuits, and, if a fault is detected, then these electrical safety devices trip circuit breakers to minimize the damage on electrical equipment. Relays monitor electrical circuits and respond to reverse power flow, over-voltage, over-current, under- and over-frequency conditions.
Electrical Safety Devices – Surge Protectors
Surge protector is an electrical safety device that protects electrical equipment against voltage spikes. Electrical equipment can be protected when these electrical safety devices try to limit any excess amount of supplied voltage by either shorting to ground or blocking extra voltages.