Electric Wiring

fidobsa wrote:

My house had hardly any sockets when I bought it so I'm putting in a few extra ones. I am doing it the same as the existing ones, chasing out the brick walls, burying plastic conduit and using individual wires for the live, neutral and earth. They don't seem to sell brown wire so I'm using black for the live. I know they use radial circuits instead of ring mains here. In UK I would normally use 4mm cable for a radial circuit but I already knew that the Schuko sockets won't accept a 4mm cable so I bought 2.5mm.... from the box to the socket?

I also rewired my own house after watching some professional bodgers doing it elsewhere and reading up on it. There's a massive amount of cavalier bodging going on in Hungary as regards electrity.

Your 2.5mm2 cable should not be multicored - each cable should be solid (see also my note on 3 phase below). If you have multicore, you can still use it but you'll have to get some ends to crimp on which is a pain. I'd recommend getting the right solid 2.5mm2 cable. You can get individual wires or you can use 3 cored cable. Individual cables are easier. You need a cable puller to get it through the conduits.

The Euro standard is indeed black, not brown these days so that's correct.

You can install a ring main if you want. They don't do it here but it makes sense to do it to avoid overloading the cable and excessive voltage drops over the length of the cable. I don't know why they don't use ring mains here other than trying to save cables. However, the extra cost is minimal if you bring the ring of sockets back to where you started and then on to the switchboard. I am assuming you know how to do the ring main.

I believe in Ireland they also use radial wiring even though they use UK plugs and sockets.

The standard cable for sockets is 2.5 mm2 and this will do you up to 7000W for the ring - 7KW is a couple of electic radiators.

You must protect the socket cable using a MCB of the right rating at the main switchboard - generally, you should stick in say, 16A. While it might seem that 7 KW would allow 30A (7000KW/230V = 30A), don't forget that cables in walls have to be derated by up to 50%. The 16A is easy to buy but higher ratings are more expensive. So use 16A to be sure. Remember the MCB is to protect the cable, not you.

Use one MCB per room/per ring main at the switchboard. Then if it jumps, you won't lose power elsewhere.

Be extremely careful about 3 phase electricity which is ubiquitious in Hungary. It'll kill you stone dead whereas a single phase could kill you as well but less likely. You need to avoid a situation where two phases might be able to come in contact with each other - deadly situation.    You can use one phase for different areas of the house where it's unlikely phases could come into contact. Note: some domestic devices like cookers and water heaters are 3 phase. These use multicored cable, 5 cores, each 2.5mm2. They use a rubber covered coating which can stand heat for that.

You can use 1.5mm2 for a seperated the lighting circuits (you can do the lights in sections of the house) and use a lower rated MCB (6 to 10A) at the switchboard. I would not use 1.5mm2 for sockets unless you can use much lower rated MCB - could cause a fire if cable is too small. Generally avoid mixing cable types to avoid confusion by anyone else fiddling with it later.

Also don't forget to install an RCD device in the switchboard. It could save your life. 80A models are quite pricey but you could use 40A.  The RCD is there to protect you, not the cable.

Finally don't forget to run the earth all the way back to switchboard. Don't connect it elsewhere as a bodge to say, a radiator or something else metallic!!

It is strange about the colours. In UK they changed the colours in the T&E from red and black to brown and blue a few years ago. The reason given was that it was to "harmonise with the rest of Europe". Of course, black was neutral in the old UK colours whereas it is live in Hungary.
Do you think if I use these crimp ends you mentioned, I will be able to get the 2.5mm into the tiny holes in the socket? I would have thought the crimps would make the cable fatter rather than thinner http://www.tlc-direct.co.uk/Technical/D … /Index.htm

The residual current circuit breaker is called "Fi Rele" for some reason I never understood, as it has nothing to do with phase offset...

fidobsa wrote:

It is strange about the colours. In UK they changed the colours in the T&E from red and black to brown and blue a few years ago. The reason given was that it was to "harmonise with the rest of Europe". Of course, black was neutral in the old UK colours whereas it is live in Hungary.
Do you think if I use these crimp ends you mentioned, I will be able to get the 2.5mm into the tiny holes in the socket? I would have thought the crimps would make the cable fatter rather than thinner http://www.tlc-direct.co.uk/Technical/D … /Index.htm

Yes, it's peculiar that it changed in the UK but hey, I never really did any substantial wiring in the UK, so I've got used to it here.  Regarding the crimped ends, it's fiddly stuff. Unless you really want to save money, you'd be better off getting a reel of 2.5mm2 solid core stuff.  OBI sell reels of cable and the crimp ends. I've never really found the crimped ends to work well. You should find they would fit in the hole.

Anyway, the solid wires will easily go in the socket. There's a kind of self locking mechanism which grips the core and stops it falling out. You have to get the exposed part, just the right length. Too long - exposed wires, too short - doesn't reach the internal grip mechanism.  I don't know how well it would work with just the crimped ends if you are persistent. I decided I wasn't going to do it that way.

One thing you might want to note is that there's a zone at the top of each room, down the corners etc which are the "cabling" zones. If you run horizontal cables, you run them close to the top of the room, about say, 10-15cm down from the ceiling, then drop vertically, usually with an access hole thing above it. These access holes are easy to put in - see below.

Another thing you might want is electricians gypsum which is like a quick drying cement for securing the conduits. An absolute whizz is what the Germans called "Blitzcement" or "lightning cement".  This stuff is great. Mix up small quantities and use it to secure difficult and funny shaped stuff. It goes off in minutes. Brilliant for putting in conduits, access holes etc. Full strength takes a few hours but works great to get things in position.  To get the conduit held temporarily while blitz cementing it, use a few old 6" nails at an angle In most HU houses, these can be tapped with a hammer into walls and they will go in perhaps 1cm. It'll give it some support while you shove the blitz cement on elsewhere (not where the nails are). After 20 minutes, you can gently pull the nails out and the cement will hold it. 

You can also get an SDS hammer drill and use a special chasing bit in non-drill, hammer mode. It's less messy than using a grinder with masonry disk.

szocske wrote:

The residual current circuit breaker is called "Fi Rele" for some reason I never understood, as it has nothing to do with phase offset...

Maybe it's a translation problem. Phase difference? Current difference? Current balance?

Thanks for the information about zones. That would be ridiculously wasteful of cable when doing the sockets at skirting board height as in UK. I suppose that is why they have the wretched things half way up the wall! I have been running the wires in channels I cut out for the central heating pipes, just above the floor. I can't get skirting board mouldings tall enough to cover these so I was going to get ordinary planed timber about 100mm by 20 mm to use as skirting board. Perhaps I should use proper office type trunking so that it is obvious there are pipes and cables there.
As for the rest of you tips, for me they come into the granny egg sucking tuition category!

fidobsa wrote:

my new sockets, a surface mount type, won't even accept the 2.5mm wire. Does anyone know what size wires these sockets are meant to take? Perhaps the idea is to run thicker cable to junction boxes then perhaps 1.5mm from the box to the socket?

As already mentioned, sockets should** accept the 2.5mm wire. Don't know if this helps or not, but if you have the type that has a button you press to insert the cable, I find I sometimes have to press it very hard down to get the internal crimp open enough to get the cable in. And for the screw down type, almost have to unscrew till the screw falls out before the cable slips in.

IMHO, 1.5 is more for fixtures, like ceiling lights where you are more certain to have a lower fixed wattage.

** This in Hungary, so I qualified it.

fidobsa wrote:

I have been running the wires in channels I cut out for the central heating pipes, just above the floor. I can't get skirting board mouldings tall enough to cover these

I personally would recommend running the wire conduits in their own channels, then just plaster over and paint. That is normally what is done. It adds stability for running wires through the conduits.

fidobsa wrote:

.... I can't get skirting board mouldings tall enough to cover these so I was going to get ordinary planed timber about 100mm by 20 mm to use as skirting board. Perhaps I should use proper office type trunking so that it is obvious there are pipes and cables there.
As for the rest of you tips, for me they come into the granny egg sucking tuition category!

Sorry about the granny eggs situation. Don't know your knowledge and of course many of the materials out here are different to those in the UK.

For the skirting, you could use tiles if you have a tiled floor. cut the tiles in half and glue them to the wall. When you grout them, any difference in height can be lost. If you use proper tile edging, it can be expensive.

I'd recommend using the zone method and not putting the cables in areas usually reserved for other services like the heating.

You can get proper office trunking in Hungary but it's quite hard to find for domestic users. You'd have to find a distributor for it. It's not as easy to find stuff here as it is in the UK, mainly due to small market and weak web presence.

Well I got the crimp sleeves today and they also don't go in the holes in the surface socket. That is without crimping though, as I don't have a tool that would compress them evenly. Pliers would squash them flat so it needs some tool like pliers with a notch of slightly smaller diameter than the sleeve. I have a ratchet crimping tool for the red, blue and yellow crimp connectors but I don't think it would do these.

fidobsa wrote:

Well I got the crimp sleeves today and they also don't go in the holes in the surface socket. That is without crimping though, as I don't have a tool that would compress them evenly. Pliers would squash them flat so it needs some tool like pliers with a notch of slightly smaller diameter than the sleeve. I have a ratchet crimping tool for the red, blue and yellow crimp connectors but I don't think it would do these.

I had the same problem which is why I said previously to get the right cable.  The cable you have is probably for an appliance which has screw terminals, not the sort you put in the walls which has solid cores.

There is another way to get the buggers to stay on and that's soldering. I also tried different types - alumnium and brass types.

Obviously, copper to brass solders well using domestic electronic type soldering irons but I no real success with the aluminium ones. I managed to tin the end of the cable to fatten it up, insert it into the crimped end and then carefully crimp it all around with pliers but I thought it was a bit dodgy and gave it up as a bad job.

fidobsa wrote:

Thanks for the information about zones. That would be ridiculously wasteful of cable when doing the sockets at skirting board height as in UK. I suppose that is why they have the wretched things half way up the wall!...

p.s. reading back through this thread, I seem to remember there's an issue or regulation with disabled people where sockets have to be halfway up the wall but I don't think that'd be the case in older HU properties. I expect that's some EU thing now. Basically someone in a wheelchair should be able to plug in stuff. There's also some other regulation on door widths (also for wheelchairs).

The crimping pliers are called "krimpelő fogó" due to criminal lack of imagination :-)
Soldering the "wick" of the multicore cable is supposedly more classy and secure than crimping though.

Aluminum cabling is generally looked down upon for unfavorable mechanical and galvanic properties, it's all copper nowdays last I heard.

Older wall sockets and light switches used screw-tightened terminals which could unscrew wide enough to fit your pinky, so I'm surprised to hear about your problems.

I have seen new, non-screw terminal blocks ("csoki", now that's a more lively name :-) ), I imagine your fixtures must have terminals similar to those.

The wire I bought is Prysmian H07V-K. The data sheets give it as the same applications as their solid core version, H07V-U:

http://www.prysmian.hu/export/sites/pry … ekek_2.pdf

I did think about soldering but that won't help get the sleeves thin enough to go in the socket! The ones I bought could be aluminium. They look silver but I assumed they were tinned copper. Aluminium would seem like a poor choice unless they are only meant for use on aluminium wire. I think you can get galvanic corrosion if you put copper in contact with aluminium.
I did use them when wiring one of the normal flush sockets. I didn't crimp them but the wires felt secure enough with the screws done up tight. They did help to prevent birdcaging of the outer strands.
I do have some old lengths of the solid core I can use for the problem socket but it all seems such a pain compared to UK wiring. I've kept trying different makes of socket to get a good quality one but even one costing 2500 Ft is rubbish compared to an old one (probably 1950s) I found in one of the outbuildings.

Thanks szocske. It looks like this is the sort I need, not cheap though:

distrelec.hu/krimpel%C5%91-fog%C3%B3k-szigeteletlen-k%C3%A1belsaruhoz/abiko/dkb-0360

fidobsa wrote:

Thanks szocske. It looks like this is the sort I need, not cheap though:

distrelec.hu/krimpel%C5%91-fog%C3%B3k-szigeteletlen-k%C3%A1belsaruhoz/abiko/dkb-0360

Why don't you just get some solid cable?

fidobsa wrote:

I've kept trying different makes of socket to get a good quality one but even one costing 2500 Ft is rubbish compared to an old one (probably 1950s) I found in one of the outbuildings.

Yes, most retail items theses days are junk. UK, US, and Germany are some of the countries, on a very short list, still making decent hardware.

If you have not tried Kopp, I recommend their hardware (http://www.kopp.eu). I purchased these a few years ago, are sturdy and work well, and were still made in Germany at my time of purchase (and I hope they still are -- but if not then look elsewhere).