Using Electricity

Houses are supplied with AC voltage of 230 V rms, at a 50Hz frequency. This is the equivalent of 230 V of DC. 

 Frequency f is a measure of how many times per second an event happens, in hertz, Hz
Period T is the amount of time one cycle or event takes, measured in seconds. 

Active: connected to voltage supply
Neutral: is connected to the neutral link at the switchboard.
Earth: Connects the appliance to the earth, as a safety device. 

Kilowatt-hour: the amount of energy transformed by a 1000W appliance when used for one hour. This number is used in calculating costs of electricity. 

 Fuse: A short length of conducting wire of strip of metal that melts when the current through it reaches a certain value, breaking the circuit. it is used as a safety mechanism to prevent a overwhelmed circuit. 

 Residual Current Device: a device that operates by making use of magnetic effects of a current to break a circuit in the event of an electrical fault.

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