“A description and explanation of the function of circuit breakers, fuses, earthing and double insulation and one other safety device commonly used in the home.”
In household circuits a number of safety methods are employed to ensure the occupants safety:
-Circuit Breakers: Circuit breakers essentially are the same as a fuse but instead of melting when the current is high, a electromagnet breaks the circuit, the advantage of a circuit breaker is that it can be reset.
-Fuses: Fuses are used so that a house doesn’t overload the circuits. A fuse is effectively a resistor with a very low melting point it is inserted in the household circuit in a series. If the resistance gets two high the fuse melts and the circuit is broken. This technique is employed to prevent the wires running through the house from heating up excessively and setting the house of fire. When the fuse melts it will be very hot so it is often kept in an insulating high melting point casing.
-Earthing: An earth wire’s function is to provide protection to the occupants of a household from electric shock when using an appliance. In a house when wiring is installed most often a very good conductor will be used earth the fuse box.
-Double Insulation: In a house hold all wires a required to be covered by an electrical insulator i.e. PVC, however some appliances such as electric shavers which are often very close to water have double insulation both on the inside and outside of the device. This safety measure is put into place so that the user is protected in the instance that the inner insulation doesn’t work.
One safety device (Seen In Photo above)
-A residual current device (RCD): Will reduce chance of electric shock, and will detect if there is any sort of leakage of currents that are traveling through your body. It will turn off the current before any harm can be done.
Relevant Link: http://www.med.govt.nz/energysafety/consumer/safe-living-with-electricity/electrical-safety-devices
-Circuit Breakers: Circuit breakers essentially are the same as a fuse but instead of melting when the current is high, a electromagnet breaks the circuit, the advantage of a circuit breaker is that it can be reset.
-Fuses: Fuses are used so that a house doesn’t overload the circuits. A fuse is effectively a resistor with a very low melting point it is inserted in the household circuit in a series. If the resistance gets two high the fuse melts and the circuit is broken. This technique is employed to prevent the wires running through the house from heating up excessively and setting the house of fire. When the fuse melts it will be very hot so it is often kept in an insulating high melting point casing.
-Earthing: An earth wire’s function is to provide protection to the occupants of a household from electric shock when using an appliance. In a house when wiring is installed most often a very good conductor will be used earth the fuse box.
-Double Insulation: In a house hold all wires a required to be covered by an electrical insulator i.e. PVC, however some appliances such as electric shavers which are often very close to water have double insulation both on the inside and outside of the device. This safety measure is put into place so that the user is protected in the instance that the inner insulation doesn’t work.
One safety device (Seen In Photo above)
-A residual current device (RCD): Will reduce chance of electric shock, and will detect if there is any sort of leakage of currents that are traveling through your body. It will turn off the current before any harm can be done.
Relevant Link: http://www.med.govt.nz/energysafety/consumer/safe-living-with-electricity/electrical-safety-devices