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Posted By: C-H Should the EU adopt the 90C rating like the US? - 07/30/03 07:00 PM
Here's another idea:

Why doesn't Europe switch from 70°C wires to 90°C wires, like North America has? If it's standard in the US it can't be expensive.

If I recall correctly, Trumpy mentioned something about halogen free cables being 90°C down under. Why not go halogen free when at it?

OK, I'll admit: I have a hidden agenda. Instead of "harmonising" current national cables, which will just confuse people, CENELEC should introduce new better ones. Just introduce the same all over Europe and nobody can complain over unnecessary harmonisation. With a common standard, prices will be kept low which means you don't need to ban the old ones. Market forces will favor the new cables.

The nationalists can go on installing EKK, PVIK and T&E.

[This message has been edited by C-H (edited 07-30-2003).]
It certainly wouldn't hurt to increase the cable ratings along the lines of NM-B in America.

With the new 3-phase color codes to be standardized across Europe, maybe a common, increased temperature rating is already in the works?

BTW, I had to chuckle the other day at the the latest batch of cable I bought. The drum had "British Standard" stamped across the top half, along with appropriate BS numbers and even a Union Flag. Around the lower half of the drum it said "Made in Republic of Ireland."
Simple reason for that.. it saves mix ups.. That cable company prob. also has IRISH STANDARD, big tricolour and IS XXXX..

They'd prob. also slap a Guarenteed Irish sticker on it [Linked Image]
http://www.lappcable.com/products/bs_cables/xlshieldfixedcable.htm
----

Core Colours:
UK:
2 core - Black and Red
3 core - Red, Yellow and Blue
4 core - Red, Yellow, Blue and Black
Ireland:
2 core - Blue and Brown
3 core - Blue, Brown and Red (What uses this???)
4 core - Blue, Brown, Red and Yellow
Sheath Colour: Light Grey



TECHNICAL DATA

Voltage:

600/1000V

Maximum Continuous Conductor
Operating Temperature:

90°C

Minimum Bending Radius:
6 x nominal cable diameter

[This message has been edited by djk (edited 07-31-2003).]
Quote
3 core - Blue, Brown and Red (What uses this???)

Maybe a switch loop where you also have an indicator which needs a neutral? Over here we'd use 3-core (red,yellow,blue) and tape the blue wire black.

Presumably if you use this 3-core blue/brown/red for a 3-phase delta connection in Ireland you tape the blue wire yellow. Correct?
Djk,

that cable is even more advanced than the specification says. It will take a lot of heat in case of short-circuit before melting and it is kinder to the environment than PVC cables.

Is it expensive?
C-H,
Your idea makes good sense, as we are all being forced (you know my view on this) to harmonize our fixed wiring colours, why not bring out new 90C cables approved for use throughout the EU.
The only potential problem would be the suitability of the equipment you are terminating into been suitable for 90C temperatures. If you are only making use of the 90C rating to reduce derating factors, eg. thermal insulation, it's an excellent idea.
BTW the steel wire armoured cables frequently used in the UK changed to 90C XLPE insulation around 8 to 10 years ago, but the flat PVC T&E types are still 70C.
Paul:

Lighting circuits here generally use conduit (behind walls) and individual colour coded cables rather than multicore cable. They don't like the idea of changing colour codes with tape. All live (or potentially live) cables will be brown in a single phase system. You could identify travellers, switch loops etc etc etc by using white rather than grey outer sheathed cable the inner sheath would still be brown) The only tape used is green/yellow stripes to mark unsheathed earth cables at junctions/switches/sockets etc.

Commercial installations often use all individual cables and trays.

In a domestic installation the circuits feeding the lighting may come out of the distribution panel (consumer unit/fusebox) as 3-core cable but the cable feeding the light fittings and switches is almost exclusively single cables.

In my opinion a much more flexible way of doing things!

The individual cables used here are very similar to the multicore cables used in the UK
single colour coded cable inside a grey outer PVC sheath.

-- It means if Mr. DIY expert opens a junction box or an electrican comes along 30 years later that the colour system is easy to follow. Brown = hot/potentially hot. Blue = Neutral and Green/Yellow stripes = Earth.

No other colours are used.


The same applied in the days of Red/Black cable too.


[This message has been edited by djk (edited 08-03-2003).]
David,
Quote

The only potential problem would be the suitability of the equipment you are terminating into been suitable for 90C temperatures. If you are only making use of the 90C rating to reduce derating factors, eg. thermal insulation, it's an excellent idea.

I agree. One could use the 70°C clipped directly values as an upper limit for current carrying capacity.

The US NEC already has similar requirements, albeit with 60C as "standard" temperature. This would also ensure that cables that are exposed aren't hot enough to harm anyone who touches them.

Quote

BTW the steel wire armoured cables frequently used in the UK changed to 90C XLPE insulation around 8 to 10 years ago, but the flat PVC T&E types are still 70C.

No such change here. All cables, except big AL cables, remain PVC 70C. That includes the new halogen free cables. Seems like you are ahead of us.

How is XLPE to work with?


[This message has been edited by C-H (edited 08-03-2003).]
Ah well, I found the maximum current on terminals. If we stick to these, there should be no problem.

Quote
Code
mm2 0.5 0.75  1   1.5  2.5  4  6  10  16  25
A   6    9   13.5 17.5  24  32 41 57  76  101


[This message has been edited by C-H (edited 08-03-2003).]
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