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Any colour you like as long as it's standardised01 July 2004Why do many people in industry seem to resent change just because it is different? A case in point is the
impending change to the cable colours used in electrical installations, writes Robert La Francesca, Marketing Manager at WeidmullerMany people in the industry are worried about the impending changes to the colours of cables, which is happening to align practice with the rest of Europe. But the change, referred to as BS 7671:2001 Amendment 2, is hardly radical as it has actually been going on since 1981.
Yet there are still those who, as well as predicting the end of civilisation as we know it, conclude that the UK will go up in electrically-powered smoke. But let us not forget that many other European countries have previously operated under different cable colour standards. They have managed the harmonisation without burning down and so should we be able to.
Furthermore, it’s not actually going to be very costly, either. Stocks of pre-harmonisation cable can be installed until April 2006, according to the provisions of BS 7671, and thus it doesn’t have to be written off for almost two years.
Most manufacturers of cabling, electrical accessories and electrical goods already operate on an international basis. Weidmuller, for example, manufactures and markets across the world, and adapts perfectly easily to the minutiae of different standards wherever on the globe we happen to be selling our goods. So, in fact, costs might actually come down with more standardisation through rationalised stock holdings.
Since the UK agreed to harmonise with CENELEC, the European Committee for Electrical Standardisation for Cable Colours, for fixed electrical wiring in 1981, we have been using blue as neutral and brown as one of (usually L1) the phase or live conductor colours in electrical appliance flexible cables, and lighting products. However, the UK is the only CENELEC country not yet using a combination of browns and blacks for phase conductors.
So now it seems only logical to extend this to fixed wiring in electrical installations as well.
The changes in colour are relatively straightforward and have been well documented by the ECA in the ECA
Comprehensive Guide to Harmonised Cable Colours (March 2004) and neatly summarised in the guide’s
accompanying wall chart.
The key table 51 from BS 7671:2001 Amendment 2 is known and has been widely published. Tables 7A to 7E in Appendix 7 of the BS cover virtually all ac and dc installations.
However, what should be further emphasised is the need for clear marking where there is uncertainty, especially during the transitional nearly two years leading up to April 2006. This is all contained in the Amendments to 514.
For example, 514-01-01 states “Except where there is no possibility of confusion, a label or other suitable
means of identification shall be provided to indicate the purpose of each item of switchgear and controlgear”. Amendment 2 also requires marking “except where there is no possibility of confusion” but this decision is up to the installer; if in any doubt, we believe it should be marked.
Use of cable markers, terminal and connection markers, with the emphasis on security of fixing, durability and legibility, is key to eradicating uncertainty at the important interfaces which might be used for isolation, where pre-harmonised and harmonised wiring meet, especially at distribution boards and switchgear. This arrangement should also be accompanied by a warning label and a circuit diagram.
Correct and clear making is essential to safety, as well as quicker and better inspection and maintenance. The best marking systems, such as our Multicard System can use computer-generated labels and a variety of printers for bespoke or standardised marking. Ready printed labels can also be bought, such as the Dekafix (DEK) markers. Applying these is quick, inexpensive and easy and the results are long-lasting.
Clear, unambiguous marking should be best practice anyway on electrical circuits. Instead of being the cause for a moan about what the EC is doing to the UK’s electrical contractors, the new harmonised cable colours should be a seen as an opportunity to get back to the quality standards we should all be aiming for. Contact Details and Archive...Related Articles...Most Viewed Articles... |
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