IET logo
 
IET
Decrease font size
Increase font size
Topic Title: Wiring colours
Topic Summary: Prefab units from overseas
Created On: 20 September 2017 12:28 PM
Status: Read Only
Linear : Threading : Single : Branch
Search Topic Search Topic
Topic Tools Topic Tools
View similar topics View similar topics
View topic in raw text format. Print this topic.
 20 September 2017 12:28 PM
User is offline View Users Profile Print this message



jammyc

Posts: 31
Joined: 25 November 2009

Hi all,

We're subcontracting on a site providing the main LV distribution to prefab industrial buildings by a Spanish contractor.

The first batch arrived yesterday and we had a quick nosey to spot any obvious problems; amongst other snags it turns out the wiring appears to be grey-brown-black-blue for L1-2-3-N respectively. I believe, but may be wrong, that that's because their implementation of CENELEC isn't the same as ours.

Obviously option A is to install as per conventional colouring, inform the main contractor of the discrepancy and agree for someone to erect signs to alert maintenance crews about the nonstandard colouring, as you might when interfacing with old school RYB.

However, our LV AC work is fairly limited to the main panel, submains and a few security systems, while the units on shipment are 90% wired in so given that nothing of ours has yet been terminated might it actually be safer in the long run for our cabling to conform to the above rotated arrangement rather than have a change in colour systems at the interface? Maybe with alphanumeric tags at each end for comfort. Would need to be clearly signed one way or the other, but for O&M teams I'd have thought consistent site rules of "It's all squiffy" would be less likely to cause confusion, espescially when circuits get added/modified/repaired come year 10.

We have no direct control over the unit contractor (and it's not our sign-off save to ensure it's safe to energise, and that's the nuclear option) so I suspect getting them to rewire isn't going to happen.

Thoughts?

J
 20 September 2017 01:20 PM
User is offline View Users Profile Print this message



mapj1

Posts: 9716
Joined: 22 July 2004

Not sure of the great problem,
Brown black grey, and
grey brown black are the same rotation sense, so no need to swap anything to make it work.
123123123 not
321321321

At most a note saying take care to check rotation and phase colours when adding 3phase loads, but I hope you do anyway.

OK your red phase is not the same as mine, but that is often true between buildings on the street mains as well, as for some reason everyone slightly overloads phase 1, so the DNOs shuffle the decks occasionally. It is only the sequence that matters.

-------------------------
regards Mike
 20 September 2017 01:25 PM
User is offline View Users Profile Print this message



CMK3PD

Posts: 70
Joined: 23 September 2016

I thought they used IEC 60445 definitions across Europe?
 20 September 2017 02:04 PM
User is offline View Users Profile Print this message



jammyc

Posts: 31
Joined: 25 November 2009

Mike,
Fair point. But because it's within a single installation I expect that it'll be queried every time the cabinets are opened/inspected.

CMK3PD
So did I until yesterday! But the chap I was with said he'd seen it so frequently (and with different suppliers) it was pretty much expected.
 20 September 2017 02:56 PM
User is offline View Users Profile Print this message



AJJewsbury

Posts: 16118
Joined: 13 August 2003

I don't know about Spain, but pre-harmonization Portugal (which I'd guess might be similar) apparently used black for L1, brown for L3 and either for L2 - see Fig 1 http://electrical.theiet.org/w...ssessment.cfm?type=pdf so I could understand if there was some local pressure not to use brown for L1 etc.

Plus of course, many on the continent never really took the trouble to distinguish between phases (often two were the same colour) - just swap two around if things would have run backwards.
- Andy.
 20 September 2017 05:40 PM
User is offline View Users Profile Print this message



kellyselectric

Posts: 192
Joined: 22 July 2016

You will know which color of ours ie red yellow or blue goes to which of theirs so just put a nice big notice saying it at the intake position and/or put tape on the ends of the European wires to clearly show whats what easy yes?
 20 September 2017 08:09 PM
User is offline View Users Profile Print this message



davezawadi

Posts: 3962
Joined: 26 June 2002

Kelly's
In case you didn't notice ours are brown black grey (clockwise rotation), but the notation is not a problem, just the rotation direction. Red yellow (white) blue, went away a good number of years ago........

-------------------------
David
BSc CEng MIET
david@ZawadiSoundAndLighting.co.uk
 21 September 2017 09:59 AM
User is offline View Users Profile Print this message



AJJewsbury

Posts: 16118
Joined: 13 August 2003

brown black grey (clockwise rotation)

Can we rely on the rotation from the L1/L2/L3 designation? (however colour coded) - I've got the impression that the rotation could be either way around, depending on where you are in the country - e.g. from my local DNO's library - http://www.northernpowergrid.c...set/0/document/103.pdf it seems that York and Middlesbrough differ from the rest of the region (section 3.5.2). Or have I mis-understood?
- Andy.
 21 September 2017 10:41 AM
User is offline View Users Profile Print this message



broadgage

Posts: 2453
Joined: 07 August 2007

DNOs have a variety of odd legacy systems with non standard phase angles and reverse rotation.
I would however expect that a standard 3 phase, 4 wire, LV supply within the customers installation SHOULD have the conventional rotation.
Near the boundary between different parts of the DNO network, the phase angle may differ from one customer to the next, but I would still expect conventional rotation and 120 phase angle between phases within the installation.

For example one should be able to wire a 3 phase socket with red or brown to L1 in any factory, and then to transport a three phase machine from one factory to another without problems. Despite any oddness within the DNO network.
 21 September 2017 02:10 PM
User is offline View Users Profile Print this message



jammyc

Posts: 31
Joined: 25 November 2009

Thanks all. Have double-checked a photo based on Andy's reply re Portugal and indeed the colourwise rotation is reversed as well as rotated. (Sorry, it was dark in there as obviously not wired up!) Does that change anyone's thoughts about simply connecting up and ensuring everything is clearly labelled?

My concern is that some unsuspecting maintenance chap may come along in ten years to replace an HVAC unit (so using existing cabling) and get mighty confused. A big sign up at the interface(s) as several of you have suggested sounds like the way forward.
Statistics

New here?


See Also:



FuseTalk Standard Edition v3.2 - © 1999-2017 FuseTalk Inc. All rights reserved.

..