The old days where house main earthing leads were green 6.0mm2. Ring "mains" were wired in 2.5mm2 T&E with 1.0mm2 earth continuity conductors. And the use of plastic oval conduit in plaster was common.
Is this compliant? Please see picture.
Z.
I'll say it. Earth is safety critical isn't it? Perhaps that ought to be red?
A bit of Teutonic thinking there by any chance?
Whilst colours are convenient, do they actually matter?
One hand they are useful, but on the other having a direct association with function is a bit limiting at times - what use is a brown/blue (or red/black) pair for a lightswitch?. Yes you can buy twin brown (but then can't tell the difference between L and SL) and it's all to messy to have a similar option with 3-core - brown/brown/brown or brown/brown/blue.
The French approach (mostly in conduit, even domestics) has a practical air about it - G/Y for PE, Blue for N and anything else you like for L. That way you can use different colours for SL, stappers, or different SLs in multi-gang switches without any need for extra labels or oversleeving.
It might be simpler if the coding simply identified the core within a cable (like the numbered cores in many cored SWAs) and the association with function was looser. You could have conventions - e,g. core 1 is perm L if present, highest number if N, if present, a separate G/Y core for PE. You could even keep colour codes, but only have them identify the cores - say using an existing colour-to-digit code (as used with resistors for example), so brown = core 1, red = 2, orange = 3 etc.
- Andy.
I'll say it. Earth is safety critical isn't it? Perhaps that ought to be red?
A bit of Teutonic thinking there by any chance?
Whilst colours are convenient, do they actually matter?
One hand they are useful, but on the other having a direct association with function is a bit limiting at times - what use is a brown/blue (or red/black) pair for a lightswitch?. Yes you can buy twin brown (but then can't tell the difference between L and SL) and it's all to messy to have a similar option with 3-core - brown/brown/brown or brown/brown/blue.
The French approach (mostly in conduit, even domestics) has a practical air about it - G/Y for PE, Blue for N and anything else you like for L. That way you can use different colours for SL, stappers, or different SLs in multi-gang switches without any need for extra labels or oversleeving.
It might be simpler if the coding simply identified the core within a cable (like the numbered cores in many cored SWAs) and the association with function was looser. You could have conventions - e,g. core 1 is perm L if present, highest number if N, if present, a separate G/Y core for PE. You could even keep colour codes, but only have them identify the cores - say using an existing colour-to-digit code (as used with resistors for example), so brown = core 1, red = 2, orange = 3 etc.
- Andy.
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