Week 8 Flashcards
neutral wire
Blue electrical wire that completes the circuit. There is no voltage on this wire.
group switch
A switch that lets you turn the voltage off for all the sockets and light fittings in a group in one go.
kWh meter / energy meter
A meter that measures the consumption of electrical energy in a house. It is also called a kWh meter because the consumption is charged per kWh (kilowatt-hour).
switch wire
Black electrical wire running from a switch to a device, only live when the switch is on the ‘on’ position.
live wire
brown electrical wire on which there is an altering voltage of 230 V.
domestic system
The network of electric wires running through the walls and ceilings of a home, from the meter cabinet to the sockets and other connections.
body resistance
The resistance of your body against electrical currents (the higher the resistance, the smaller the current).
earth wire
A copper wire with green-and-yellow striped insulation that connects the socket’s earth connection to a pin that has been driven into the ground.
overloading
Running too many devices from a single group, so that the total current is greater than 16 A.
contact resistance
The resistance at the points where the current enters and exits the body (the greater the resistance, the smaller the current).
group fuse
A device that turns the current off if the current in the group goes above 16 A.
earth leakage circuit breaker
A device that compares the current in the live wire against the current in the neutral wire. If the difference is greater than 30 mA, the earth leakage circuit breaker will turn off the power. There is then no longer a leakage current.
double insulation
A way of insulating appliances in which two layers of insulation are used: one around the components that the current is passing through and one on the outside of the appliance.
short circuit
A fault in a circuit that allows the current to find an easier path from the live wire to the neutral wire (that is, one where the resistance is much too low).
