Ring Main at Consumer unit

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.


It is this kind of discussion caused by this thread, which shows up shortcomings in our EICR procedure very clearly, and this is only for a simple domestic installation, not a much more complex one elsewhere. It is why the experience of the inspector is very important, and why he needs to set the standard in the right place. That place is not "Is there any conceivable way this could be dangerous", and must be "is there any reasonable way this defect could be dangerous" DUE only to that defect. If one adds damage etc. on top of the defect, everything is dangerous, one must use a reasonable likelihood for damage. This is usually firmly indicated by the installation method and accessory construction, for example, steel conduit and metal-clad fittings. Without this clipped direct wiring must always be given a C2, as damage is reasonably possible by accident and deliberate action.


Many of the EICRs I see that are "excessively coded" are because this threshold is not understood, it may be deliberate, but I am sure that many are due to misunderstanding, in fact, some of the electricians concerned seem genuinely surprised that their EICR is too harsh. It becomes much clearer when their own work is examined and coded in the same way, minor deviations being just slightly imperfect work. The tails in question may have been pulled quite hard because they were rather short to reach the new meter terminals, which might well be the cause of the requirement for metal CUs in the first place. The problem is caused by poor management of meter installers, they do not have Henly Blocks available and are not supposed to open CUs. How is the problem of short tails resolved?


Looking at Youtube has become somewhat horrific. There are a number of videos on CU changes, the look of the job is obviously of great importance to the posters, all neat and straight and square wiring etc. Lovely. Is this specified by BS7671? Not really, nothing wrong with tidy work, but in most of the videos, it is obvious that none of the old wiring is being used. Not a CU change then, but a complete rewire or extension of the old wiring (which they do not show). That is the job that separates the men from the boys.


You may find it interesting to listen to the Grenfell tower inquiry videos on youtube, running daily at the moment. It is very legalesque, but some bits are interesting in that so many steps, in the safety inspections were not followed properly. It is not that they were just poor inspections, it is the follow-ups that are poor, to say the least. Several other points have also shown up, inadequate training, false claims of competence, false qualifications (or ones which were not held listed as post-nominals, letters after the name), all of which are commonly committed by some electricians. I wonder how many of you are "Registered Electricians"  (used by a local firm)? You may be registered with a competent person's scheme, but that doesn't have the same ring about it, does it?

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.


It is this kind of discussion caused by this thread, which shows up shortcomings in our EICR procedure very clearly, and this is only for a simple domestic installation, not a much more complex one elsewhere. It is why the experience of the inspector is very important, and why he needs to set the standard in the right place. That place is not "Is there any conceivable way this could be dangerous", and must be "is there any reasonable way this defect could be dangerous" DUE only to that defect. If one adds damage etc. on top of the defect, everything is dangerous, one must use a reasonable likelihood for damage. This is usually firmly indicated by the installation method and accessory construction, for example, steel conduit and metal-clad fittings. Without this clipped direct wiring must always be given a C2, as damage is reasonably possible by accident and deliberate action.


Many of the EICRs I see that are "excessively coded" are because this threshold is not understood, it may be deliberate, but I am sure that many are due to misunderstanding, in fact, some of the electricians concerned seem genuinely surprised that their EICR is too harsh. It becomes much clearer when their own work is examined and coded in the same way, minor deviations being just slightly imperfect work. The tails in question may have been pulled quite hard because they were rather short to reach the new meter terminals, which might well be the cause of the requirement for metal CUs in the first place. The problem is caused by poor management of meter installers, they do not have Henly Blocks available and are not supposed to open CUs. How is the problem of short tails resolved?


Looking at Youtube has become somewhat horrific. There are a number of videos on CU changes, the look of the job is obviously of great importance to the posters, all neat and straight and square wiring etc. Lovely. Is this specified by BS7671? Not really, nothing wrong with tidy work, but in most of the videos, it is obvious that none of the old wiring is being used. Not a CU change then, but a complete rewire or extension of the old wiring (which they do not show). That is the job that separates the men from the boys.


You may find it interesting to listen to the Grenfell tower inquiry videos on youtube, running daily at the moment. It is very legalesque, but some bits are interesting in that so many steps, in the safety inspections were not followed properly. It is not that they were just poor inspections, it is the follow-ups that are poor, to say the least. Several other points have also shown up, inadequate training, false claims of competence, false qualifications (or ones which were not held listed as post-nominals, letters after the name), all of which are commonly committed by some electricians. I wonder how many of you are "Registered Electricians"  (used by a local firm)? You may be registered with a competent person's scheme, but that doesn't have the same ring about it, does it?