Installing RCBO Query

True, but there is another side to this - that unless/until RCBOs come with appropriate 'indicators', their use (as opposed to RCD+MCB) means that it is not apparent (let alone 'immediately obvious') whether the fault on the circuit was one of over-current or earth leakage.

More nonsense
 
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Not permitted, as the existing RCD is a Type AC, which is no longer permitted for anything other than fixed equipment which has no DC components - basically resistive heaters and nothing else.

Even more nonsense

There is nothing stopping anyone doing that
 
Even more nonsense ... There is nothing stopping anyone doing that
As I wrote, not 'nonsense' but, to my mind, an illustration of how silly it can be to 'blindly worship' the regulations.

The OP is under no obligation to do anything about his lighting circuits which have no RCD protection. It therefore makes no electrical sense for him 'not to be permitted' to, for one of thee circuits, to change that situation (no RCD protection) to one in which it is protected by a Type AC RCD, which is quite obviously would bee a 'beneficial change' (in terms of theoretical 'safety').
 
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As I wrote, not 'nonsense' but, to my mind, an illustration of how silly it can be to 'blindly worship' the regulations.

The OP is under no obligation to do anything about his lighting circuits which have no RCD protection. It therefore makes no electrical sense for him 'not to be permitted' to, for one of thee circuits, to change that situation (no RCD protection) to one in which it is protected by a Type AC RCD, which is quite obviously would bee a 'beneficial change' (in terms of theoretical 'safety').

It’s the advice by Flameport that is nonsense.

As I stated there is nothing stopping people continuing to use set ups like the op has.

Flameports content could be used to convince people that their set ups are dangerous - which is misleading to say the very least
 
The cost difference these days is much smaller and you’ll recoup that the first time you have a problem as it’s immediately obvious which circuit is faulty
Agreed, I hate it when I see Dual boards instead of RCBOs, I saw one in new flats recently, nice big flush impressing looking consumer unit and , to my mind, the duality spoilt the board.
Having said that, I am a front-ender = I have two consumer units (Normal and off peak) both with a front end 30mA RCD Mainswitch. Compliant at time of install, in fact quite common back then, there was even an article in "Wiring Matters" a few years later stating that they were compliant in the authors opinion too.
But, for many years, I have based my estimates on dual boards but given a highly recommended option of RCBOs and have 1000% successfully persuaded the customers to have RCBOs, in fact if they had declined I would have walked. In the early days they were a very expensive option though, so understandably took a while to take off to normality.
I, as yet, remain unconvinced about AFDDs.
 
True, but there is another side to this - that unless/until RCBOs come with appropriate 'indicators', their use (as opposed to RCD+MCB) means that it is not apparent (let alone 'immediately obvious') whether the fault on the circuit was one of over-current or earth leakage.
Agreed - I did see one make that considered this, well sort of! The RCBO switch had half way and full way trip positions to differentiate which element (RCD or MCB) had tripped but the householders just looked upon it as either tripped or not tripped therefore not really a success I thought.
 
Not permitted, as the existing RCD is a Type AC, which is no longer permitted for anything other than fixed equipment which has no DC components - basically resistive heaters and nothing else.
Agreed
 
As I wrote, not 'nonsense' but, to my mind, an illustration of how silly it can be to 'blindly worship' the regulations.

The OP is under no obligation to do anything about his lighting circuits which have no RCD protection. It therefore makes no electrical sense for him 'not to be permitted' to, for one of thee circuits, to change that situation (no RCD protection) to one in which it is protected by a Type AC RCD, which is quite obviously would bee a 'beneficial change' (in terms of theoretical 'safety').
Quite so. Absolutely agree. (Actually, it might be the case that Flameport actually agrees too but purely for clarity he has pointed out the correct stance on this issue, not that I assume that but I have some suspicion that it is possible that it might be the case here though and I`d say top marks to him for that stance).

Actually, a few years back, I attended a lecture by somebody very high up in a knowledgeable way about electrical regulations and practices when discussing what we should and should not do. His stance seemed very pedantic to a few of us in the know. A half hour later we were having a one to one about a totally different subject and I referred back to his previous statements with a "So you home is up to date then?" to my surprise he confided with some slightly revealing details "Oh no, not by a long way, I live in a rented house!" and he gave a heart chuckle. He knew his onions to the letter and taught as such but in reality he lived in the real world.

It would be beneficial for me to update my consumer unit but it`s been front end 30mA RCD for many years without "false/nuisance tripping" problems so far.

Oh and I do test it regularly, actually S W M B O checks it quite often with the overfill of steam iron test too :giggle:
 
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As I stated there is nothing stopping people continuing to use set ups like the op has.
Continuing to use what they have (no RCD on the lighting circuit) is not the same as adding a type of RCD which is specifically prohibited from use to an existing circuit in the belief it will somehow improve it.

Now cue in 'no less safe', 'they worked for years', 'it's better than it was before' and other things which really are nonsense.
 
Quite so. Absolutely agree. (Actually, it might be the case that Flameport actually agrees too but purely for clarity he has pointed out the correct stance on this issue, not that I assume that but I have some suspicion that it is possible that it might be the case here though and I`d say top marks to him for that stance).
You may well be right, and that might apply to a lot of the statements he makes. However, as I often write, my concern is that his 'simplifications' (if that's thie deliberate intent) often come over as authoritative assertions, which are likely to be taken as 'gospel' by many readers in view of his (justifiable) reputation.

The word "nonsense" has been thrown about a lot in recent posts. What I personally regard (would regard) as nonsense is for regulations that do not 'require' any increase in safety of an existing circuit to 'not permit' changes which increase safety, simply because they don't go quite as far as current regulations would require.

Kind Regards, John
 
Continuing to use what they have (no RCD on the lighting circuit) is not the same as adding a type of RCD which is specifically prohibited from use to an existing circuit in the belief it will somehow improve it.
Agreed, it's not thee same thing. However, as I've just written, given that no improvement is 'required', it seems illogical that a change which results in increased safety should be 'prohibited' simply because it does not 'increase safety' quite s much as current regs would require.
Now cue in 'no less safe', 'they worked for years', 'it's better than it was before' and other things which really are nonsense.
I'm not sure exactly what you're saying, but my view above remains. I presume that you must agree that a Type AC RCD is better ('safer') than no RCD, even if a Type A one would be theoretically even better.
 
If the 10A lighting MCB had originally been fitted on the RCD side it would have been compliant and state of the art, now a few years on it would still be compliant. Moving from its current position to the RCD side would be absolutely no different and if it hadn't been mentioned on here no-one would have any idea that it had not always been like that.


It's not quite the same But I'll try to make a comparison:

The brake on one wheel of a car has worn below the friction pads limit (according to a book somewhere) to the point it has no braking effect, is it safer to leave it as it is or adjust it?
I know it's not the same situation, but both scenarios did work and did comply with all requirements and (if the lights are in a rental property) now neither does.
Please do not pick holes in my offering, I know they are not a proper comparison.
 
Continuing to use what they have (no RCD on the lighting circuit) is not the same as adding a type of RCD which is specifically prohibited from use to an existing circuit in the belief it will somehow improve it.

Now cue in 'no less safe', 'they worked for years', 'it's better than it was before' and other things which really are nonsense.
It reminds me of people exclaiming that the old electric fire they had since the days of Vera Lynns War and the one before it and it always worked OK but now you put an RCD on it does not work. The RCD is faulty cos my fire has always worked (Yes I have actually had people say things like that and some other choice gems from time to time). Flameport is absolutely correct. I doubt that he would ever reveal whether or not he would feel very slightly slightly happier for an appliance to have an AC RCD on rather than no RCD at all.
I will stick me neck out and admit that yes I would, slightly but I would feel a lot happier with the correct RCD being there instead. I come from an era where RCDs (including ELCBs) were virtually unheard of and none of us were too alarmed. Many years later we have become used to RCDs being the norm and yes we`ve seen/heard of them being very effective, then even us old gits would feel a certain apprehension of no RCD or an incorrect RCD.
In fact, in my case, if it`s a TT situation I feel happier with 2 RCDs in tandem rather than reliance on just one, preferably in slightly different places environmentally speaking if that is not too difficult to achieve and yes tested frequently by test button and at least 5 yearly or shorter with a proper tester , not just to check it`s acting at all (test button) or acting within time (test meter) but might well be a way of lessening the the effects of "Stiction" I`d rather an RCD mechanism have a better chance of free movement than being slowed down a few millisecs because of stickiness .
I feel that the old 2 RCD boards for TT system (100mA delayed action for all circuits plus a 30mA non delayed one for power circuits) had a possible slight advantage under the wrong conditions (OK I know if you are holding a Live part it`s the 30mA one that`s likely to save you but if the fault occurs more than a few seconds before you touch it and it`s likely to try to exceed 100mA then I see that as another fighting chance to save some poor sod).
It does worry me though that some folk envisage an RCD as a "Saviour to all" rather than still taking sensible precautions as if an RCD was never invented. That would be as daft as driving a modern car with all of its safety devices including seat belts then driving like a total maniac - oh hang on though, some folk do just that!
 
The brake on one wheel of a car has worn below the friction pads limit (according to a book somewhere) to the point it has no braking effect, is it safer to leave it as it is or adjust it?
Quite so. Doing something which improves safety but not to the extent reequired by 'rules' has surely got to be better than leaveing an undafee/'less safe' situation?

To extend your analogy, what if one replaced the worn pads which "had worn below the friction pads limit (according to a book somewhere) to the point it has no braking effect," with second-hand pads which, although still "below the friction pads limit (according to a book somewhere)", had not worn to the extent of impairing breaking effect? That would be 'not permitted' but would nevertheless represent a major improvement in safety, hence surely better than 'doing nothing'?

I am not advocating the undertaking of 'not permitted' work, but think that these are discussions which need to be tempered with a fair chunk of common sense !

Kind Regards, John
 

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