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Appliances

Do you know how much electricity you use per day? Your bill is the meter readings for a number of days, the Kw/Hours or units used. The used kW on your bill is divided by the number of days gives you the daily consumption. How do you know what appliance to use sparingly? Which appliance consumes most power?

Calculators

Some electricity suppliers give free devices to calculate the power consumption, but you know this from your bill! What you don’t know which appliance used what amount of energy. Appliances using the conventional plug and socket can use the plug/socket power calculator available in the market place giving adequate information for under £10 in the sales, supply voltage, current used, mains frequency, wattage, volt amps, power factor, kWH.

Voltage

Named after “Voltaire” and in the UK is still 240Volts AC and can vary above and below this value.

Current

Taken by the appliance from the mains in amps named after “Amperes”

Watts

Is the “Real power” the appliance consumes based on Voltage and amps in a restive load “like a wall heater” is the power in “watts” and per hour is the units used, kWH.

VA	Is the “Apparent power” consumed by a non restive (like a wall heater) with a motor such as a vacuumed cleaner. Inefficient use of power and required power correction to make the motor look like a heater.

Hertz

The frequency at which the electricity is delivered and in the UK is 50Hz or 3000 rpm of the generator. “Hertz”

Power Factor

PF is the correction required to reduce the current taken by a motor or fluorescent light to reduce the power consumption. The power correction deals with the current as the voltage is fixed the current can be altered. Reduce the current reduces the power taken by the appliance with a maximum nearly 0.95, the closer to 1 is approaching true power.

kWH	Is the power consumed by the appliance watts used every hour or units used reflected on the electric meter.

Clock

Is the time the metering is measured over, the vacuumed is on for 20 minutes the clock will reflect that which means the kWH can be calculated. The vacuum consumes 1400W for 20 minutes being 1/3 of an hour consumes 1400/3 = 470kWH or 0.47U and left on for an hour will consume 1.4U. With the vacuum the power factor will come into play as it is a motorised appliance.