Calculating amperage for plugs

Given you know the wattage to be consumed, the voltage of your local home’s power grid (most commonly 230V in Europe, but you should look it up! No space for assuming here), and the amperage of the plugs you have installed in your plugs cabinet, you can then calculate which of the outlets you can use for your power consumption.

Prerequisite knowledge

  • Amperage (\(A\)) of the already installed plugs. Good idea grasp the inventory of used plugs so you can map which outlets has a certain (shared) amperage to use. Common amperage of plugs are: \(6A, 10A, 16A\)

  • Voltage (\(V\)) of your home’s power grid. Common voltage in Europe is: \(230V\)

  • Wattage (\(W\)) of the equipment you wish to power. Lights usually hover around the lower dussins of watts, while electric radiators usually use around \(1000W\)

Calculating wattage

Wattage is calculated by \(W = A \times V\).

So let’s say you find in your plug cabinet three plugs that all take different amperage. You also find a note besides the cabinet describing their use case.

Living room lights\(6A\)
Radiator, hallway\(10A\)

How much wattage \(W\) will the stove plug actually allow? Well. Let’s take out our formula again and plug in the numbers:

$$ \begin{align} W &= A \times V \\ &= 16_{A} \times 230_{V} \\ &= 3680_{W} \end{align} $$

If your stove’s manual says it can use up to \(1500W\), that means you can then install another (identical) stove on an outlet that uses the same plug!

Calculating the wattage of all of the above listed \(6A\), \(10A\), and \(16A\) plugs, it would give us the maximum wattages of \(1380W\), \(2300W\), and \(3680W\), respectively.

Can I just swap my current plugs?

Let’s say I just want to install my new console (that for sake of argument can use up to \(1500W\)) in the living room, and plug it in to an outlet that goes to the living room lights, can I just swap my current living room plug out for a \(10A\) plug?

No. Leave it to the professionals. Read more on why you should Never change a plugs amperage#