Why different voltages?

Voltage varies all over the world, but there are two main voltage “camps” 100-120V and 200 – 240V.

The country that uses the lowest standard voltage in the world is Japan at 100V and the highest is the UK at 240V.

100V-120V is used in US, Canada, Japan and most of North and South America as well as Taiwan. There are a few odd exceptions such as Mexico where the voltage is 127V.

200-240V is used in the rest of the world, although confusingly there are a few countries with dual voltages such as Saudi Arabia (127V and 220V), Tahiti (110V and 220V) and Madagascar (127V and 220V).

Generally, most appliances are built within a tolerance, so anything that works in the UK at 240V will also work in other European countries at 230V, 220V or even 200V.

The whole idea that voltage is fixed is a myth anyway, and the voltage within a country can vary slightly from day to day and place to place.

There is some debate about why the big differences arose, but generally the Americans seem to have chosen 110 as a way of standardising the different voltages used by the early lighting companies. While in Europe they chose a higher voltage probably due to cost reasons.

One thing you cannot do is use a 220-240V appliance in a 100-120V country or vice versa. To do this you would need a Voltage Converter (also known as a Voltage Transformer). To use a 220V appliance in a 110V country you would need a Step Up Voltage Converter, i.e. the converter raises or steps up the voltage from 110V to 220V. To use a 110V appliance in a 220V country you would need a Step Down Voltage Converter, i.e. the converter lowers or steps down the voltage from 220V to 110V.

There are Voltage Converters available that can be used as either Step Down or Step Up Converters. These converters have some kind of selection switch somewhere on them.