Shed Wiring Question

[EFLImpudence]

Perhaps they do regard a circuit from an FCU as a new circuit but for some reason decided not to make it notifiable.

 

[JohnW2]

Perhaps they do regard a circuit from an FCU as a new circuit but for some reason decided not to make it notifiable.

Who knows (but, were that the case, they should have done something other than write that 'new circuits', without qualification, were notifiable!) - but are you suggesting that they may have decided to make it non-notifiable if it were an off-the-shelf FCU, but notifiable if it were an 'emulated' one?

Kind Regards, John

 

[EFLImpudence]

Who knows?

Referring to the pre-relaxed (still Welsh) notification requirements, or rather non-requirement, was the term used not "fused spur" with no mention of the method of fusing so could include the emulated?

That a lot of people (wrongly) call the FCU itself a fused spur can only exacerbate the situation.

 

[EFLImpudence]

With regard to including the fused spur separately on a certificate, I have done that in the past when the job was only the fitting of the fused spur - for a fan.

It was queried by the annual assessor (who agreed with Bas) but I still disagree with him.
As my work only involved the spur that was what I recorded.

Also, although it was not the case, the Zs at the fan could be too high for the 32A MCB.
Therefore I can see no alternative to recording it as I did and see no difference if, as was the case, the Zs would have been satisfactory for the MCB.

 

[JohnW2]

Who knows? ... Referring to the pre-relaxed (still Welsh) notification requirements, or rather non-requirement, was the term used not "fused spur" with no mention of the method of fusing so could include the emulated?

It was ....

2. Work which -
(a) is not in a kitchen, or a special location,(b) does not involve work on a special installation, and(c) consists of -
(i) adding light fittings and switches to an existing circuit; or(ii) adding socket outlets and fused spurs to an existing ring or radial circuit;...

If, as you seem to suggest, you feel that this was meant to (or could) include (and hence maybe still includes) 'emulated' FCUs, then that would obviously render 'wide open' the discussion I've been attempting to have with BAS.

That a lot of people (wrongly) call the FCU itself a fused spur can only exacerbate the situation.

Indeed, but it is plain silly to argue (as some have been known to do in the past) that those 'old' (in England) rules allowed an FCU (the accessory) to be added without notification, but that connecting anything to its load terminals would turn it into notifiable work!

Kind Regards, John

 

[EFLImpudence]

Indeed, but it is plain silly to argue (as some have been known to do in the past) that those 'old' (in England) rules allowed an FCU (the accessory) to be added without notification, but that connecting anything to its load terminals would turn it into notifiable work!

That was my point; they didn't mention FCUs the term was:

"adding socket outlets and fused spurs to an existing ring or radial circuit" was allowed.

The fused spur is the circuit, not the accessory.

 

[JohnW2]

Also, although it was not the case, the Zs at the fan could be too high for the 32A MCB.

It could indeed - but if you were regarding (and recording) it as a separate circuit, then the Zs would only have to be low enough to satisfy the requirements of that circuit's OPD - a (probably 3A) BS1362 fuse.

Therefore I can see no alternative to recording it as I did and see no difference if, as was the case, the Zs would have been satisfactory for the MCB.

As above, the Zs could theoretically have been far too high for the upstream circuit's MCB but adequate for the OPD of what you were regarding and recording as a separate 'circuit'. By analogy, you don't have to ensure that a circuit has a low enough Zs to satisfy disconnection times on the basis of the DNOs fuse if, as will be the case, there is some other lower-rated OPD downstream of the DNO fuse. In practice, of course, if the main circuit's Zs was already satisfactory, then, AFAICS, nothing is gained (or altered) by regarding (and recording) the post-FCU bits as a separate circuit.

Kind Regards, John

 

[EFLImpudence]

Also, although it was not the case, the Zs at the fan could be too high for the 32A MCB.

It could indeed - but if you were regarding (and recording) it as a separate circuit, then the Zs would only have to be low enough to satisfy the requirements of that circuit's OPD - a (probably 3A) BS1362 fuse.

Quite - but I was told by the assessor that I should have recorded the details of the ring circuit not my spur.

 

[JohnW2]

That was my point; they didn't mention FCUs the term was: ... "adding socket outlets and fused spurs to an existing ring or radial circuit" was allowed. ... The fused spur is the circuit, not the accessory.

Exactly my point, too. Let's assume (I think very reasonably) that the same still holds - i.e. that the 'relaxations' (in England) in 2013 did not turn any of those previously non-notifiable things into notifiable ones.

With that assumption, I think we can probably agree that adding two or more FCU's side-by-side, supplied by the same existing circuit and supplying various new wiring/loads, is not notifiable? Agreed?

Next, you seem to agree that if we used side-by-side 'emulated FCUs' (each with a fuses {for the moment, let's say ≤13A}, and maybe a switch, in an enclosure), instead of off-the-shelf FCUs, that would still be OK? Agreed?

So next, we put the fuses (and perhaps switches) of those two or more 'emulated FCUs' into a single enclosure? Has it yet suddenly become notifiable? (I would personally say not)

So, we now have fuses, in suitable holders, and probably switch(es), in a single enclosure, each fuse supplying one or more new loads. That more-or-less constitutes a DB (although obviously not a type-tested CU). If, rather than fabricate my own, I go out and buy a customised DB/CU which has two or more fuse holders and a 'main switch', has adding that now suddenly become notifiable?

... and finally (perhaps the most contentious step), if we replaced the fuse holders and fuses with MCBs, what then? 'Suddenly' become notifiable? Although the 'old' (in England) rules did talk about 'fused spurs', they could well have been using that term generically, since I can see no reason why the OPD could not be an MCB rather than a traditional fuse.

... and "finally, finally", what if some of those MCBs have an In >13A. Does that change anything?

Kind Regards, John

 

[JohnW2]

Quite - but I was told by the assessor that I should have recorded the details of the ring circuit not my spur.

Hmmm. You surely have to record, amongst other things, the 'worst case' that exists anywhere in the circuit (including any spurs it may have). I don't think it would be contrary to any regs, per se, to have a fused spur in which the cable downstream of the FCU was incredibly long, such that the Zs at the end of that spurred cable would be much greater than anywhere on the ring itself. That surely needs to be measured, recorded and 'considered for acceptability', doesn't it. Indeed, any spur (fused or unfused) originating close to the middle of a ring final may well have a Zs higher than would be measured anywhere on the ring itself - you surely weren't being told to ignore that, were you?

Kind Regards, John

 

[EFLImpudence]

Quite - but I was told by the assessor that I should have recorded the details of the ring circuit not my spur.

Hmmm. You surely have to record, amongst other things, the 'worst case' that exists anywhere in the circuit (including any spurs it may have). I don't think it would be contrary to any regs, per se, to have a fused spur in which the cable downstream of the FCU was incredibly long, such that the Zs at the end of that spurred cable would be much greater than anywhere on the ring itself. That surely needs to be measured, recorded and 'considered for acceptability', doesn't it. Indeed, any spur (fused or unfused) originating close to the middle of a ring final may well have a Zs higher than would be measured anywhere on the ring itself - you surely weren't being told to ignore that, were you?

I agree that a fused spur was not notifiable (I don't know why) and it is the circuit (cable) that is the spur so any type of fusing may be used.

However, I do also think that it is a separate circuit and so, presumably, is also new.

Whether it is still not notifiable because of the previous (schedule 4) ruling or not, I haven't the faintest idea.

 

[EFLImpudence]

Don't know where the underline and italics came from???

Quite - but I was told by the assessor that I should have recorded the details of the ring circuit not my spur.

Hmmm. You surely have to record, amongst other things, the 'worst case' that exists anywhere in the circuit (including any spurs it may have). I don't think it would be contrary to any regs, per se, to have a fused spur in which the cable downstream of the FCU was incredibly long, such that the Zs at the end of that spurred cable would be much greater than anywhere on the ring itself. That surely needs to be measured, recorded and 'considered for acceptability', doesn't it. Indeed, any spur (fused or unfused) originating close to the middle of a ring final may well have a Zs higher than would be measured anywhere on the ring itself - you surely weren't being told to ignore that, were you?

No, not being told although he thought I should.

I disagreed and still do and refused to alter it.

 

[JohnW2]

I agree that a fused spur was not notifiable (I don't know why) and it is the circuit (cable) that is the spur so any type of fusing may be used. ... However, I do also think that it is a separate circuit and so, presumably, is also new. ... Whether it is still not notifiable because of the previous (schedule 4) ruling or not, I haven't the faintest idea.

{I've got rid of the underlining and italics for you ]
Fair enough, but, as I've said, don't you agree that it's very unlikely that the intention was that the 'relaxations' (in England) would render the addition of (previously non-notifiable) fused spurs notifiable - i.e. that they probably remain non-notifiable (in England as well as Wales)?

You're probably nervous about invoking the wrath of BAS but do you agree with me, on the basis of what I previously wrote, that if installation of one or more 'fused spurs' (supplied by existing circuits) is still not notifiable, one can argue logically and rationally that a 'CU' (emulated, hence logically also 'off-the -shelf') fed from an existing circuit should also not be notifiable?

Maybe you could answer the questions in my 3:17pm post (hover your cursor over the 'X minutes ago'!) on the assumption that the addition of fused spurs is still non-notifiable in England?

Kind Regards, John

 

[EFLImpudence]

I agree that a fused spur was not notifiable (I don't know why) and it is the circuit (cable) that is the spur so any type of fusing may be used. ... However, I do also think that it is a separate circuit and so, presumably, is also new. ... Whether it is still not notifiable because of the previous (schedule 4) ruling or not, I haven't the faintest idea.

Fair enough, but, as I've said, don't you agree that it's very unlikely that the intention was that the 'relaxations' (in England) would render the addition of (previously non-notifiable) fused spurs notifiable - i.e. that they probably remain non-notifiable (in England as well as Wales)?

I do agree that it is unlikely but unlikely does not seem to rule out some things.

You're probably nervous about invoking the wrath of BAS but do you agree with me, on the basis of what I previously wrote, that if installation of one or more 'fused spurs' (supplied by existing circuits) is still not notifiable, one can argue logically and rationally that a 'CU' (emulated, hence logically also 'off-the -shelf') fed from an existing circuit should also not be notifiable?

I thought I had already answered that (and invoked any wrath) by saying that the previous list of non-notifiable work included fused spurs without specifying which fuses may be used and that a fused spur is not an FCU.

Maybe you could answer the questions in my 3:17pm post (hover your cursor over the 'X minutes ago'!) on the assumption that the addition of fused spurs is still non-notifiable in England?

I would logically assume that it is still not notifiable merely because it wasn't but I do not know why because I consider it to be a separate and therefore new circuit.


Perhaps the authors also thought an FCU was/is a fused spur and that was all they intended to exempt but, as is frequently the case, that was not what they wrote.
It has just occurred to me that an unfused spur was notifiable but was/is not a new circuit.

 

[JohnW2]

I thought I had already answered that (and invoked any wrath) by saying that the previous list of non-notifiable work included fused spurs without specifying which fuses may be used and that a fused spur is not an FCU.

Yes, but that was just in relation to 'fused spurs' probably/presumably still being non-notifiable. However, I was really asking whether you agreed with my step-by-step extrapolation from that (presumption) to saying that an enclosure containing a switch and OPDs (aka a 'CU'), fed from an existing circuit, was also probably non-notifiable?

It has just occurred to me that an unfused spur was notifiable but was/is not a new circuit.

Was it (notifiable)? ....

or(ii) adding socket outlets and fused spurs to an existing ring or radial circuit;...

Do you not think that "adding socket outlets ... to an existing ring or radial circuit" would include unfused spurs? Indeed, in the case of a radial, any added socket could, if one so wanted, be described as a 'spur' (I personally don't use the term in relation to radials unless it is a 'reduced CSA spur').

Kind Regards, John