Rating of Electrical Appliance:These are normal rating of electrical appliances available in the market.
Electric bulb-100W, 60W, 15W
Fluorescent tube- 40W, 20 W, 80W
CFL lamp- 5W, 15W, 20 W, 40W, 90W
Refrigirator- 220 W
Micro Oven- 3000 W
Electric Iron- 700W
Induction Heater - 1500 W
From the rating of the electrical appliance , we can calculate the resistance of the filament, current flowing through the filament.
Also electrical energy consumed (WHr) can be calculated by multiplying the watt and duration of time in hour.
By converting the energy into bigger unit i.e. KWHr , the practical unit consumption of our houses can be find out. This is called KWhr or unit of electrical energy.
Today's average rate of electricity is around Rs 7.50 / unit.
It means if 200 unit reading is on the electric meter. It means we need to pay 200*7.5+ constant charge for maximum demand.
Rs 1500+ 100 = Rs 1600 approx.
The constant charge varies for maximum demand allowed during new connection.
Calculation of unit consumed:
For example let 500 watt load is running in our house for 8 hours. Then unit (KWHr) consumed will be
500 W x 8 hr
=4000/1000 KWhr = 4 KWhr