why are there different shapes of electric plugs around the world why isn’t there a universal one

266 views

why are there different shapes of electric plugs around the world why isn’t there a universal one

In: Engineering

In Australia, our wall outlets are 240volts

In places like the USA it’s 110 volts (I believe)

They’re designed as to not be plugged into the wrong supply

As with many things that have different [standards](https://xkcd.com/927/), different people come up with different ideas independently. Then someone says “There are too many different plugs. I’m going to make a new one that everyone will use.” Now there’s just an extra standard.

However, the different plugs also act as a safety feature since the different countries have different voltages and frequencies of electricity. Different plugs means you can’t put one device into something designed for another. Why these different voltages? See paragraph 1.

Part of it has to do with different current standards; to avoid people plugging in, say, an appliance using 120V 60Hz AC in an outlet delivering 210V 50Hz AC. That would be bad for the device.

As for why different plug shapes exist in countries with synchronized electric grids – the grids weren’t always synchronized, and different regions developed their own preferred plug designs before voltages were standardized across the continents. It was just easier to keep the old standard plug shapes and use travel adapters than to rewire every building and appliance in the land.

For more info on the different plug standards, see https://www.worldstandards.eu/electricity/plugs-and-sockets/

Even in the US alone, you have many different plugs for different purposes. Different factors include:
Single, split, or 3 phase.
Presence or absence of a ground wire.
Current rating.
Voltage.
Locking vs non-locking.

So yeah, that’s how you get dozens of different kinds of plug, even in a single country.

Across the world, different countries developed their electric grids at different times, and came up with local standards that made sense for them. The standards are still different because if what you have works it’s difficult to justify tearing everything out and replacing it.

* Older electrical systems use lower voltage and higher current.
* Newer systems use higher voltage and lower current (for increased safety and other reasons).
* Upgrading older systems would be far too costly.
* Plugging equipment designed for the older systems into the newer systems could destroy that equipment and could start dangerous fires.
* Differently shaped plugs help to avoid that.