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Calculate Fuse Ratings

There is a formula for working out the fuse rating, voltage or wattage for each appliance

P (Power in Watts) = V (voltage) x I (current in Amps)

The fuse rating can be calculated by dividing the power used by the appliance by the voltage going into the appliance.

I (Amps) = P (Watts) ÷ V (Voltage)

To calculate the fuse rating for a 1KW (1000 watts) appliance, divide the wattage (1000) by the voltage (230).

I (Amps) = P (Watts) 1000 ÷ V (Voltage) 230

I (Amps) = 4.35

A five amp fuse would be required.

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