Garage wiring question.

[JohnW2]

one always has to be aware of the possibility that "someone ignorant and incompetent may have been fiddling with the electrical installation", even if one has not (yet) seen any evidence of that.

True, but when convincing evidence is found.....

There is another possibility - that the person concerned was neither ignorant nor incompetent but, rather, 'cautious' - i.e. having installed a 2.5mm² ring final circuit, and (maybe) knowing that the OPD could be changed for 32a one if ever required, used a 16A for the time being because (s)he knew that such was more than adequate for present purposes. ... not really any different from installing 10mm² cable (for 'future proofing') for a shower circuit but currently protected it with a 32A OPD since the current shower is only 7.5kW (at 240V).

I suppose it comes down to the question of whether, in the absence of concrete evidence, one wants to "assume the worst of people" or "assume the best of people". (i.e. whether people should be regarded as guilty until proved innocent, or vice versa).

Kind Regards, John

 

[ban-all-sheds]

I think that when their worst might kill me, I'd rather assume the worst.

 

[JohnW2]

I think that when their worst might kill me, I'd rather assume the worst.

So that would be "guilty until proved innocent", then? As I said a couple of posts back, I think you typed "We" when you should have typed "I"!

Kind Regards, John

 

[ban-all-sheds]

Well - if you want to carry on picking at it, then what I should have typed was "True, but IMO nobody in the OPs position should ignore the waving red flags and loud alarm bells ringing which tell them that at some point someone ignorant and incompetent has been fiddling with their electrical installation."

If you want to criticise that as "guilty until proved innocent" then go ahead - I won't make any apologies for it, because that attitude could save someone's life, whereas "innocent until proven guilty" could cost one.

 

[JohnW2]

If you want to criticise that as "guilty until proved innocent" then go ahead - I won't make any apologies for it, because that attitude could save someone's life, whereas "innocent until proven guilty" could cost one.

Indeed so - in the same way that if we locked up for life everyone who was suspected of possibly having committed a murder, we would undoubtedly prevent some future murders, and thereby save some lives - whereas requiring that there is strong evidence of guilt before we lock them up for life will equally undoubtedly cost some lives (future victims). I can't disagree.

Kind Regards, John

 

[nobbynomates]

Wow, That escalated a little!

So its safe, although not done quite correctly, it needs the lighting circuit down fusing with an FCU and 3a fuse?

Am i better off replacing the 16a RCD with a 32a?

Am i within the rules to do this work myself?

 

[JohnW2]

Wow, That escalated a little!

That tends to happen around here

So its safe, although not done quite correctly, it needs the lighting circuit down fusing with an FCU and 3a fuse?

On the basis of what we've been told, it sounds essentially safe, certainly once a 3A FCU has been interposed in the feed to the lighting.

Am i better off replacing the 16a RCD with a 32a?

I presume you mean MCB, not RCD? If 16A (total, including lighting) is adequate for your needs, then nothing would be gained by 'upgrading' it. If you do/might want/need more than 16A, then you could have the MCB 'upgraded' (potentially to 32A). However, although from what you've told us there is no obvious reason why a 32A MCB could not be fitted, you would really be advised to get an electrician to check the circuit to make sure that there is not some reason why, unusually, a 16A MCB has been fitted.

Am i within the rules to do this work myself?

Anyone is allowed to do any electrical work, so long as they are adequately competent to do it safely, and we are not really in a position to judge whether that would be true of yourself. Certain electrical work is 'notifiable', but that would not apply to this. If you are reasonably competent/comfortable, then it may well be reasonable for you to add the lighting FCU yourself. Changing the MCB is rather different - if you are not familiar and competent in working within a CU, that is probably best left to an electrician (for your own safety). As I said, it would make sense to get an electrician to check out the circuit if you were contemplating upgrading the MCB - and if (s)he said that a 32A MCB would be OK, then it would probably only take him/her a small amount of additional time to actually do it for you. However, as above, if 16A is adequate for your current needs, you might as well stick with it - it can always be upgraded later if the need arises.

Kind Regards, John

 

[ban-all-sheds]

Indeed so - in the same way that if we locked up for life everyone who was suspected of possibly having committed a murder, we would undoubtedly prevent some future murders, and thereby save some lives - whereas requiring that there is strong evidence of guilt before we lock them up for life will equally undoubtedly cost some lives (future victims). I can't disagree.

I don't suppose you can.

And I don't suppose you can understand that the consequences for a former house owner considered "guilty until proven innocent" of possibly leaving a dangerous electrical legacy for future owners aren't quite in the same league as those for people locked up for life because they are considered GUPI of possibly having committed a murder, can you.

 

[bernardgreen]

I recall plug in fuses in fuse boxes where the size of the hole in the fue box ensured that only the right fuse holder would go into that position. Colour coded with dots on the holders.

Perfect......except that 30 amp fuse wire could be fitted to a 5 amp fuse holder.

The point is that it is possible to protect against the idiot who wants a 30 amp fuse on 5 amp wiring.

There also ignorant people who do not understand or know anything about electrical safety.

There are also criminals who intentionally ignore the rules for their own benefit.

Nothing can be 100% safe or risk free. The best is to try to educate people and encourage them to learn, understand as best they can and then act sensibly.