GENERATION OF ELECTRICITY
THERMAL POWER STATION
GAS TURBINE POWER STATION
GEOTHERMAL POWER STATION
NUCLEAR POWER STATION
SOLAR ENERGY
BIOMASS POWER PLANT
WIND ENERGY
Transformers (sometimes called "voltage transformers") are devices used in electrical circuits to change the voltage of electricity flowing in the circuit. Transformers can be used either to increase the voltage (called "stepping up") or decrease the voltage ("step down"). A transformer is just a piece of iron with a pair of wires coiled around it - one with many more turns in the coil than the other. The coils of wire are not physically connected. The iron core is immersed in an insulating oil bath which does not conduct electricity well.
ELECTRICITY TRANSMISSION AND DISTRIBUTION SYSTEM
THERMAL POWER STATION
Step up transformer
11kV
275kV
National grid network
Switch zone
HYDROELECTRIC POWER STATION 25kV
Houses
Local sub station
Main sub station
240V
Light/heavy industries
Heavy industry
11kV
33kV
ELECTRICAL SUPPLY AND WIRING SYSTEM AT HOME
CABLE TYPE
NOTE
LIVE/ACTIVE Carries electricity into the WIRE house NEUTRAL WIRE
Carries electricity from the house back to the power station.
TYPES OF CIRCUIT
1. LIGHTING CIRCUIT 2. RING MAIN CIRCUIT
3. POWER CIRCUIT
PARTS IN ELECTRICAL WIRING SYSTEM
FUNCTION
1. LIVE WIRES
Carries electricity from local substation to houses (240V)
2. NEUTRAL WIRES
Completes electrical circuit from house back to local substation. (0V)
3. ELECTRICITY METER
Measure how much electricity is used in the house
4. MAIN SWITCH
Cut off main supply when doing major major repairing job in the house
5. FUSE
Cuts off circuit if excess current passes through
6. CIRCUIT BREAKER
Turn off electricity automatically if too much current/short circuit occurs
7. FUSE DISTRIBUTION BOX
Distribution points for house electricity supply
ELCB
The power and voltage rating of home electrical appliances. 1.The rate at which an appliance uses energy is called power, measured in watts (J/s) 2.The amount of current flowing through an electrical appliance: POWER = VOLTAGE X CURRENT P = VI 3.Electrical energy used at home is measured by: ELECTRICAL ENERGY = POWER X TIME (KwH) (Kw) (H) 4. Cost of electrical used = total domestic units x tariff rate.
Cartridge fuse (1A, 2A, 5A, 10A, 13A) Rewirable fuse (5A, 10A, 15A, 30A)
PRECAUTIONS IN ELECTRICITY
PRECAUTIONS IN ELECTRICITY
PRECAUTIONS IN ELECTRICITY