ECN Forum Forums General Topics of the Trade Non-US Electrical Systems & Trades Some german electrical info

Hi PaulCornwall,

i live in Bavaria. Which cable system do you mean is flex?

Outlets in bathroom are allowed, but there are specified areas where that is not allowed. (next to showers, tubs, there are exact distances, dont have these in mind) and a RCD with trip current <30mA is prescribed for the bathroom.

Andy,
just looking at that 10 mm2 solid wire makes my hand hurt. How on earth do you bend such a beast?

Why do Germans insist on solid wire? Stranded (not fine stranded) is much easier to work with in sizes 2.5 mm2 and up. It's probably safer than the solid too, since it puts less force on the terminals. Admittedly, I'm not an electrician.

Paul, Cornwall,

Sweden didn't allow sockets in bathrooms until a few years ago. So perhaps the question "still allow" should be "already allow"?

[This message has been edited by C-H (edited 10-19-2003).]

Hi C-H,

it's hard but you can do it

i agree with your fact of the mechanical stress on the terminals.

but i think its OK touse solid ones for 1,5 and 2,5mm² house installs. They are easy to use with the clamp-terminals (there are even Breakers with cage claps at the load side now), and 95% of Schuko outlets and light switches sold today use this system. Although i heard you may use stranded wires in these, i wouldnt trust it.
using stranded wires on screw terminals, most do-it-yourself enthusiasts would use them without ferrules, damaging the copper and making the terminal a hot spot. i have seen horrible things with these from selfmaking guys. banged the screw into that terminal and cut 75% of the copper strands.....

Sweden uses the same devices as Germany (or did until Swedish-made devices forced them off the market) but 1.5 mm2 stranded wires for the in wall wiring. Ferrules are not used.

For some reason, cables - identical to NYM - use 1.5 and 2.5 mm2 solid. The 1.5 mm2 is no problem, the 2.5 mm2 is a bit trickier but still workable. Larger wires are invariably stranded.


[This message has been edited by C-H (edited 10-19-2003).]

C-H, what do you use to connect the stranded wires in junction boxes? wirenuts? as they have a metal thread inside? doesnt this damage the strands?

Yes, in in-wall boxes you use wirenuts, wagos or in the case you are out of space "u-boats" [a single screw, single pole terminal block]. In surface installations, a box mounted terminal block is sometimes used.

Does it damage the wires? Yes. You can't reuse the wires more than once or twice before you have to cut them back since you have lost some strands. Wagos appear to be even worse. Fortunately, you do not very often change installations. Otherwise, the wires would be very short very soon.

[This message has been edited by C-H (edited 10-19-2003).]

see, that kind of safety risk with cutted strands can't appear when only using solid. Wirenuts even cut into the solid wires, but a stranded wire with the outer strands cut off can be pulled out of the nut. a solid wire is held good because of the cut.

the u-boats are what i meant with the brass cube. and using them with stranded not-ferruled wires is really a safety risk IMO.

[This message has been edited by :andy: (edited 10-19-2003).]

Hi Andy

just spotted the picture of the cable i thought was flex, that on the smaller sizes must be easy to use, we use a flat cable called twin and earth, generally in domestic work, and its rubbish, i dont under stand why we dont use a round cable over here.

I cant belive you guys can put sockets in bathrooms,, we have just had a regulation update on bathrooms here, and we can just about put a light in there, we will be back to candles over here.

the thought of someone putting a tv on a stool whilst having a bath, then leaning out to change channels.........

Flex is rare in fixed wiring here. Even cables suitable for a 45A cooker tend to be solid. You litterally need to use tools to bend them.

They're relaxing a little where stranded cable is allowed but it must be correctly finished with a ferrule simply twisting the strands together isn't regarded as sufficient.

Heavy flex is often used in DIY jobs though.

Oops! My apologies. I shouldn't have made that silly mistake, as I do know the difference betweeen der/die/das.

I'm not sure if my ISP has an incoming limit for attached file sizes, but I've never had any problems receiving 1MB+ attachments, so for our purposes there shouldn't be any difficulties.

C-H:
You bet! I can feel my wrists aching just thinking about shaping that. Any bigger and we'd need to use a conduit bender to form the wire into shape!

In the older British cables (before about 1970) we were at the other extreme. Only the very smallest size (1/.044, almost equivalent to modern 1.0 sq. mm) was solid. Everything else was stranded: 3 strands for the next two sizes and 7 strands for the other common domestic sizes.

By the way, American Romex now has a ground wire the same size as the other conductors, but British "twin & earth" still has the earth one size smaller, e.g. 4mm cable has a 2.5 earth. (The exception being 1.0 cable which has a 1.0 sq. mm earth.)

"Flex" is used in British English as a shortening of "flexible cord." It refers to cords with a fine-stranded wire, such as the top and middle cords in your second photo.

On the color code issue, the U.K. had a similar problem when the European colors were adopted for flex, as blue was (and still is) used as a phase in fixed wiring.

We had quite a discussion on color coding a while back:

https://www.electrical-contractor.net/ubb/Forum9/HTML/000081.html


[This message has been edited by pauluk (edited 10-19-2003).]