Ring Main at Consumer unit

davezawadi (David Stone):

You are doing it now Chris.

Tails identified with the old colours are not a C3 by any reasonable test. There should be a label saying that mixed colours may be present, quite why that is needed is also dubious now, although when the change took place perhaps necessary. There is no need whatsoever to improve the wire colour codes. A black/red cable from a switch drop should have a red or brown sleeve on the switched live (black) but this may be given a C3, it is somewhat inconvenient when a ceiling rose is replaced. C2 is not somewhere between a C1 and C3 either, it is for potentially dangerous as you know very well, which the examples above are not, at least in the normal sense of danger. C3 is for regulation non-compliances which are not dangerous if you like that definition. A plastic CU in a domestic is not dangerous, it is potential loose screws which may be, so we code it as a C3. The inspector should check the screws and is then sure this problem is not present in the CU, thus C3. A plastic CU is perfectly permissible in other premises, so this requirement is somewhat anomalous, however, we seem to have it.

Well, C3 if there is no colours notice. I must say that Daughter was somewhat alarmed when I slapped a "WARNING" notice on her CU. ?


Notice or not, there is no need to replace the tails (or other cables) - just put those coloured (+/- lettered) cable ties around them. Not too difficult to rectify the grommet and sheath either.


I fully agree that a plastic CU (at home) is only C3 (the power to this tablet arrives via one) but what of those loose screws? In testing them, do we not tighten them? Or having found them loose, do we return them to the condition in which we found them? Yes, that's a bit absurd!

davezawadi (David Stone):

You are doing it now Chris.

Tails identified with the old colours are not a C3 by any reasonable test. There should be a label saying that mixed colours may be present, quite why that is needed is also dubious now, although when the change took place perhaps necessary. There is no need whatsoever to improve the wire colour codes. A black/red cable from a switch drop should have a red or brown sleeve on the switched live (black) but this may be given a C3, it is somewhat inconvenient when a ceiling rose is replaced. C2 is not somewhere between a C1 and C3 either, it is for potentially dangerous as you know very well, which the examples above are not, at least in the normal sense of danger. C3 is for regulation non-compliances which are not dangerous if you like that definition. A plastic CU in a domestic is not dangerous, it is potential loose screws which may be, so we code it as a C3. The inspector should check the screws and is then sure this problem is not present in the CU, thus C3. A plastic CU is perfectly permissible in other premises, so this requirement is somewhat anomalous, however, we seem to have it.

Well, C3 if there is no colours notice. I must say that Daughter was somewhat alarmed when I slapped a "WARNING" notice on her CU. ?


Notice or not, there is no need to replace the tails (or other cables) - just put those coloured (+/- lettered) cable ties around them. Not too difficult to rectify the grommet and sheath either.


I fully agree that a plastic CU (at home) is only C3 (the power to this tablet arrives via one) but what of those loose screws? In testing them, do we not tighten them? Or having found them loose, do we return them to the condition in which we found them? Yes, that's a bit absurd!