Thread by @tech963

What's this old Swiss plug? Why is it special? And finally, why is it not used anymore and what replaced it?

Read below to find out more...
(a thread 🧵)

This is a Swiss T14 plug, which is identical to the T2 plug, the original Swiss earthed plug introduced in the 1930s.

And, as you might have noticed, it doesn't use a pin for the earth connection. Instead, the socket itself had an earth pin.

This is different from how most other plugs and sockets around the world work - with one exception...
The French plugs also have an earth pin on the socket!

However, T2/T14 plugs are not the same as the French ones.

The earth pin spacing is different, and the T14 plug is narrower so a French plug wouldn't work in the same socket.
However, it's interesting that those are, as far as I know, the ONLY two types of sockets that were used in normal houses which use an earth pin.

This is actually a pretty big deal, because as far as plugs go there isn't really a lot that can change. Sure, the shape, size and position of the pins can change, but generally most (earthed) plugs are all the same: they have 3 pins on them. But that's not the case here.

There is ONE exception to that rule and that is a plug that doesn't even have pins on it: the BTicino Magic plug.

But... that one is a completely different beast altogether, and it deserves its own thread.
I wrote more about it on my site: samuele963.github.io/other/electric…

Anyways, back to the T14 plug: I have one socket that accepts it and it's this one.

However, you can probably see how the socket also seems to be made for a plug with an earth pin! So why's that?

Well, the problem with T2/T14 plugs is that they could be inserted into unearthed T1 sockets.

I don't have one of them, but I can simulate the same situation with this BTicino Domino socket. The socket doesn't have an earth connection, but the plug fits in anyways.

(sidenote: it's EXTREMELY useful that most European plugs and sockets had the same pin spacing, with the only difference being sometimes the thickness of the pins. The major differences only came in once earthed plugs were introduced)

Anyways, so in 1953 they introduced the T12 plug, the current Swiss standard. It uses an earth pin on the plug itself, it was more compact, and (depending on the type of the socket) some T12 sockets could also accept T1 plugs.

So, it was definitely an improvement.

And so this is the reason why this socket has a hole for the earth pin on a plug: this is a hybrid T14 socket! So it accepts both T14 and the more modern T12 plugs.

That made a lot of sense, obviously you wanted to use both old and new appliances, so this was perfect for that!
According to the plugsocketmuseum.nl T14 sockets were available until 1975, so this one is definitely older than that, and it shows.

Nowadays T14 plugs are very uncommon in Switzerland, and modern T12 plugs have sleeved pins and a recessed socket, making them extremely safe (especially compared to the US standard).

So this is it! This a brief look at the old Swiss T14 plugs, and a brief look at the modern T12 ones.

I should add some extra things about the more modern Swiss standard:
First of all, the neatest thing about it is that bigger sockets are compatible with smaller plugs - so a 16A socket works with a 10A plug, and even a three phase socket works with a single phase plug.

Additionally, the Swiss standard is perfectly compatible with Europlugs, which means that even though we use different plugs for earthed devices in Italy, I can still bring my phone charger along with me on a holiday.

Anyways: this is it! Thanks for reading all the way through this thread! I hope it was enjoyable. I try to write threads like these every once in a while so stay tuned for more :)

If you enjoyed it, consider RTing it so others can see it as well!

I also made this other thread about electrical items, in this case they were plugs from Italy

https://twitter.com/tech963/status/1368956276072386568

Finally, I cannot thank the plugsocketmuseum.nl enough for all the amazing work they've done to preserve the history of these old plugs! It's how I figured out what that Resista socket was, and it's where I got most of the info for this thread. Definitely worth checking out!

If you're interested in old electrical items, I wrote more about them on my site: samuele963.github.io/other/electric…
And on my channel:
youtube.com/channel/UC8qgL…

Thanks for reading through this thread! 💙