Wiring: which type of wire ?

[Warichet]

Hi,

I've a Hager Univers electric cabinet
So far, I've used solid wire 2,5² for the internal wiring. As the supply is 3 phases, I've used a color for each phase.
Now I hear that flexible wire 2,5² is more suited, mainly for heat dissipation. This argument makes sense, plus the flexible wire is much more comfortable and easy to install.

Which type of wire is recommended for the internal wiring of the UV ? solid vs flexible ?
I guess it has more to do with "good practices" than regulations.

Thank you for your advice

[MarkusS]

I think there is no simple answer.

I started with solid wire (because the electrician told me to do so because he thought "solid is better" and he was used to solid wire), at some point I switched to flexible wire.

One electrician uses solid wire, the second electrician uses flexible wire with simple cable end sleeves, the third one uses flexible wire with cable end sleeves with "collar". From my experience, beyond 2.5 mm2 any electrician uses flexible wire because solid wire in about 10 mm2 is very hard to handle.

In my opinion, flexible wire is more comfortable and easier to handle - but you might need cable end sleeves which require additional - more or less expensive - tool(s). I use a (not so cheap) Weidmüller PZ3 crimping tool which has the advantages that there is only one universal crimping terminal for 0,5-6 mm2 and that the crimped cable end sleeve is very compact (important for some cage clamps).

I prefer cable end sleeves with "collar", the collar protecting (insulating) the blank copper where the wire enters the connector, preventing someone accidentially touching live wire.

Usually, you are allowed to connect one wire per connector (please refer to manufacturers technical product information about how many and which type of wire might be connected - variants might be: solid wire, flexible wire, flexible wire with cable end sleeve). On the other hand, I had to connect several wires to one connector - on a circuit breaker for example or on a cage clamp. Using cable end sleeves, it is possible to connect two flexible wires in one cable end sleeve (have a look at the grey twin cable end sleeve in the middle of above picture).

So, speaking for Germany and having said that I'm not a trained electrician: As far as I know, there is no regulation requiring the use of solid or flexible wire within a cabinet (in buildings, there might be different regulations for e.g. machines). But usually, the manufacturer of a specific device specifies which type (diameter, solid or flexible) and number of wire can be connected to this device.

[Warichet]

Hi Markus,

I think there is no simple answer.

Thank you for this detailed explanation.
An what is your opinion about "flexible wire 2,5² is more suited, mainly for heat dissipation" ?
Is it really an argument ? Although I can understand that the external surface of a solid 2.5² is much smaller then the total surface of 10 wires of 0,25², although yelding the same gauge.
I'm considering ripping out everything and start from scratch, but the argument is a bit weak.

[anlo007]

Hi Raymond,

in the German DIN (see https://knx-user-forum.de/showthread.php?t=3452 list end of page 1) there is no difference between solid wire and flexible wire.

I prefer solid wire, because it is faster to mount without the end sleeves and you can push them into WAGO-typ termination blocks or connectors, when you need more wires in 1 terminaton.

The flexible are easier to lay in plastic cable-channels.

Both types are equally accepable and the 2,5² diameter you are using gives enough reserve on a 16 A fuse, as you can see in the a.m. list.

regards
Andreas

[thieleks]

is this really an issue ??

as long as you don't have to deal with continous-flow water heaters eg., I can't imagine that you have any thermal problem with 2,5 mm²


In Germany, for example, inside your cabinet you may use 1,5 where the external wire has to be 2,5, due to better cooling of single flexible OR solid wires

Best regards,

Klaus-Peter

[Warichet]

in the German DIN (see https://knx-user-forum.de/showthread.php?t=3452 list end of page 1) there is no difference between solid wire and flexible wire.

OK, I can understand, the regulation specifies the section of the wire. It doesn't say how this section has to be obtained. Hence, the topic is open.

I prefer solid wire, because it is faster to mount without the end sleeves

Oh well, that's an argument for a craftsman, doing many installations. But for a private person, the time is not very important, but the quality of the end-result is .

you can push them into WAGO-typ termination blocks or connectors, when you need more wires in 1 terminaton.

OK, but I use the DIN Wago, which accept solid & flexible wires.

The flexible are easier to lay in plastic cable-channels.

Yes, indeed. The Hager Univers has those plastic cable-channels to route wires from rail to rail.

is this really an issue ??

Heuuu, don't know, that's why I'm asking the experts. So you tell me.
I got contradictory information, and can't make my own opinion.

In Germany, for example, inside your cabinet you may use 1,5 where the external wire has to be 2,5, due to better cooling of single flexible OR solid wires

OK, quite clear.
Anyway, for some actuators I had to use 1.5², a 2.5² wire wouldn't fit.

Thank you for your comments.