Type J-F hybrid sockets? Swiss/Eu? What the?

3 Apr 2021
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I have always had an interest in electrical works and have no problems wiring a new plug or working out how to add a new light socket to the circuit etc. I’ve lived in the UK for most of my life and as most know UK follows good rules and regs with wiring. Spain on the other hand...

I have recently moved into an apartment in Spain only to find that 20% of the plugs are your standard type F and the other are what look to be type J with a round inlay but not as recessed as a type F (see pics I’ve looked and I can’t find this type of faceplate so the closest to compare is a type J). what the hell is this thing? there all over the house...

First thing I wanted to do when I moved in was work out what each breaker on the switchboard does as nothing is labelled and to know what runs where given this weird arrangement of type Js and Fs

Breakdown breakers-

The far right is orange and is the main breaker. The two furthest left power the lights and all the old type J sockets.. old school Spanish wiring. The next one is for the oven, the other I’m not sure? I couldn’t find it.. and the last powers the type F sockets, now interestingly I can’t turn just the oven on for example without also having to keep the furthest left breakers on as well (the lights and type J). Or the same with if I just power the type F breakers the furthest left need to be on also?

Things don’t seem right here... I tried plugging a mid power device (1000w heater) into the type J and F plugs to see if I can see any flickering lights.. when I plugged them into the dodgey type J plug and turned it on it did infact flicker and each crank of the heater drove the lights slightly dimmer. when I plugged it into the type F plug sockets it didn’t.

Given this situation. I am ok to plug high power devices such as heaters etc. into the type F sockets although it’s on a separate breaker BUT still routing over the lights and type Js..

Also throwing it out there as im no expert/ am I ok to just use the type J sockets for mid range power devices even if it’s still on the same circuit as the lights?

Any recommendations and insight would be great

Thanks! Or should I say gracias ☺️
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It looks like the right hand (orange) breakers are the "current limiters" which relate to your contracted supply with the electricity provider. You will see that they are marked C16 which is a 3.3KW supply, and the breaker is a "C" curve. I would guess the 15A breaker is "Alumbrado" or lighting, the 20A breaker the water heater and/or washing machine ("lavado") and the 25A various sockets ("otros usos"). The implication is that the 25A breaker to the left of the RCD is not RCD protected, so that needs looking at! In my flat in Spain, about half the sockets (all Schuko) are on the 10A lighting circuit and the remainder on the 16A otros usos. Tread carefully! HTH

Oh, due to the fact that Schuko plugs are reversible, the regulations require double pole breakers at the distribution board.
Oh, due to the fact that Schuko plugs are reversible, the regulations require double pole breakers at the distribution board.
I don't know if the Spanish regulations do require that but that's surely not a valid reason.
Actually the second breaker from the left is the RCD (after doing some more research) and as I said the left-most breaker is the lights and all the Swiss plugs, then they have added additional breakers on that same circuit (I can’t turn off the left breaker and still test the oven for example) So I think they routed everything through the 25A leftmost plugs which is also feeding the oven and newer EU sockets but at least they have a lower amped breaker running through a bigger amp breaker through the RCD.. and you want to see the wiring.. viva la espanol ;)
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Just for the sake of anyone reading this in the future, as I’m sure it’s long resolved, the sockets pictured at an obsolete Spanish grounded 3-pin type that was once commonly installed in some regions of Spain.

They are similar to Swiss 3-pin plugs (Swiss plugs will even fit the sockets) but the pins were wider and they were rated, like modern Schuko for 16amps and the plugs had sleeves on the pins.

Schuko plugs often fit these but the earth connection isn’t made, which is quite dangerous if you’re using a Class 1 appliance, like a kettle, or a coffee machine or a metal bodied major appliance, like a washing machine etc.

You can still get the plugs for these (much like you can still buy plugs for old UK round pin sockets in England) but, similarly it indicates an older installation would be recommended that you get your wiring upgraded, and have normal Schuko sockets fitted instead.

You can encounter some other odd regional variations in old Spanish wiring, including very obsolete (pre 1960s) French 3 pin sockets and something compatible with present day Italian 3 pin plugs, in all cases this means an old / obsolete installation.

Non grounded 2 pin plugs will, of course, fit all of these. So for small appliances like TVs, mobile chargers or non grounded stuff like hairdryers and vacuum cleaners they work quite safely (but might not provide finger protection, due to lack of a recessed design.

In general though, if your house has sockets other than Schuko, get a survey and an upgrade.
Also btw the reversible plugs are nothing to do with the 2-pole breaker requirement. The MCB will always be on the live no matter what way you insert the plug. So that’s not really relevant.

It only matters if there’s a fuse in the plug, as in the UK and Ireland, because if you reversed a UK plug you’d have the fuse on the neutral and the appliance possibly on a 32 amp ring, with no fuse!

It’s irrelevant on European style radial circuits, as there’s no need for plug fuses. All that’s taken care of at the distribution board (consumer unit) and the live is always the live in fixed wiring.

2 pole breakers and switching depends largely on the supply type and how the network’s neutral works.

In the UK, Ireland, and quite a lot of countries TN-C-S (or variants of that) almost universally used or very dominant. These are systems in which the neural conductor is grounded at multiple points along the route from the transformer to the house. They therefore don’t need to switch or fuse the neutral. (It may even be not allowed in regs.)

In some countries TT (or IT) is the most common - France for example. These allow for simpler network wiring, but can have a risk of a floating neutral that’s at a different potential to the local Earth reference. The live to neutral potential the will always be ~ 230V, but neutral to Earth may have a potential other than 0V.

So, for that reason, the all circuit breakers cut both live and neutral and the neutral conductors in all European (including UK) appliances is to be treated as potentially live for this reason and the likely use of reversible plugs or figure of 8 appliance connectors, is assumed in all appliance design under CE / EU regs.

In modern installations, those kind of TT installations are usually also protected by a master higher rated RCD (for fire safety reasons) in addition final circuit RCDs (for personal protection).

Incidentally, even in the UK and Ireland TT is encountered in some areas where, usually due to soil conditions (high Earth loop impedance), TN systems aren’t practical. So the design philosophy is still useful as a universal convention in appliance design, even where the polarity is pretty much guaranteed in some countries.

Anyway, sorry if it’s a bit of a long historical and techie post but, just wanted to clear up a few common misconceptions and people often read these threads years after they’re posted :)