Jobsworth

[stillp]

We also don't know that it isn't damaged, so it's all supposition. Anyway, an IR test would not prove the absence of damage to the insulation.

It wouldn't - but it would indicate that any damage to the insulation was not presenting any immediate danger to life, limb or property

No it wouldn't! The insulation could be missing on a section of the line conductor without causing a low IR. Would you say that was safe?

 

[JohnW2]

It wouldn't - but it would indicate that any damage to the insulation was not presenting any immediate danger to life, limb or property

No it wouldn't! The insulation could be missing on a section of the line conductor without causing a low IR. Would you say that was safe?

I didn't actually say 'safe', but if the test were undertaken after the work had been completed (switches replaced, no cables exposed or accessible, and all exposed-c-ps earthed, Zs OK) I certainly wouldn't see it representing an "immediate danger to life, limb or property" (on re-energisation), would you?

Kind Regards, John

 

[sparkwright]

Don't know if we've used the expression yet, but I think we are talking about simple 'like for like' replacements.

 

[mfarrow]

There has been drift, introducing problems, e.g. no earths and metal switches, but that's a very different situation.

The situation is no better here. You have no recognised fault protection on the cable. Granted changing the switch won't make the installation worse, but it's a matter if integrity.

If you're asked to replace a lighting circuit with all new cables except the switch drops 'cause that would ruin the decorating, would you accept it? What if those switch drops had no CPC and metal switches hanging on the end?

If someone asked you to replace the plug on an appliance but the sheath was missing on half the cable, would you be happy to do this? Would you expect your scheme to support your decision if you did?

 

[sparkwright]

There has been drift, introducing problems, e.g. no earths and metal switches, but that's a very different situation.

The situation is no better here. You have no recognised fault protection on the cable. Granted changing the switch won't make the installation worse, but it's a matter if integrity.

If you're asked to replace a lighting circuit with all new cables except the switch drops 'cause that would ruin the decorating, would you accept it? What if those switch drops had no CPC and metal switches hanging on the end?

If someone asked you to replace the plug on an appliance but the sheath was missing on half the cable, would you be happy to do this? Would you expect your scheme to support your decision if you did?

You wouldn't rewire a lighting circuit leaving unsafe switch drop cables in. You would find a way the existing wiring could be made compliant, failing that you would turn the job down. No one in their right mind would install a new circuit with known dodgy old wiring connected to it. Trunking or ceiling pull switches would be about the only alternative.

In fact what I would do here it fit remote controlled switches, with the receiver near the light.

If half the sheath was missing on an appliance where I was changing the plug, I would replace the flex, or if not practical, use an in-line flex connector. This would be such a simple and cheap thing to have to do it wouldn't be an issue.

 

[JohnW2]

The situation is no better here. You have no recognised fault protection on the cable. Granted changing the switch won't make the installation worse, but it's a matter if integrity.

I think some thought needs to go into what 'integrity' means in that sentence - since the more I think about it, the less sure I am. Is it necessarily a sign of 'integrity' to be effectively responsible for a situation in which the householder may well have to turn to a 'less reputable' electrician, or do the work themselves when, as you say, if it were done competently by a 'reputable electrician', it would not make the installation worse?

If you're asked to replace a lighting circuit with all new cables except the switch drops 'cause that would ruin the decorating, would you accept it? What if those switch drops had no CPC and metal switches hanging on the end?

That's very different. No-one would expect an electrician to actually do work (install unearthed metal switches) which was not only overtly non-compliant with current regs but also potentially dangerous.

Kind Regards, John

 

[ban-all-sheds]

Quite John. The problem is that we haven't seen the installation in question, and I don't think BAS has either.

No, I haven't, but the only thing the electrician has seen which he is unhappy about are these singles at switch positions.

The single insulated singles, and the cut-back sheath, might be minor examples in a whole plethora of faults,

They might be, but see above.

Perhaps the insulation was damaged when the sheath was cut back

It might have been, but see above

 

[ban-all-sheds]

As I understand BAS's OP, its "either/or" - it appears to be single-insulated singles, but it could be T+E with the sheath cut back too far (although I'm a bit confused, because the nature of the CPC ought to distinguish between those two possibilities!).

Ah - sorry.

Some of the switch drops are in singles and no sign of conduit, or T/E with the sheath cut back too far

I meant that some of the switch drops are in singles and no sign of conduit, and some are T/E with the sheath cut back too far.

 

[JohnW2]

Ah - sorry. ..... I meant that some of the switch drops are in singles and no sign of conduit, and some are T/E with the sheath cut back too far.

Ah! Thanks for clarifying.

Kind Regards, John

 

[ban-all-sheds]

No it wouldn't! The insulation could be missing on a section of the line conductor without causing a low IR. Would you say that was safe?

It could be, and not necessarily.

BUT: If you are concerned about that then logically you cannot ever make any additions or changes to any installed circuits because you can never know if there's damage like that somewhere you can't see. Just as you could not tell from testing if there's a short section of bell wire in a socket circuit. Anybody who says "Ooh - I can't do anything to a circuit unless I can be sure it complies with the regulations (or complied at time of install)" cannot logically do anything except install new circuits or replace old ones, unless he can inspect every single bit of it.

 

[ban-all-sheds]

The situation is no better here. You have no recognised fault protection on the cable.

Do you mean mechanical protection?

If you're asked to replace a lighting circuit with all new cables except the switch drops 'cause that would ruin the decorating, would you accept it? What if those switch drops had no CPC and metal switches hanging on the end?

What if you noticed that somehow but weren't doing work on the circuit? To what extent would you be unprepared to have anything to do with any of the installation?

If someone asked you to replace the plug on an appliance but the sheath was missing on half the cable, would you be happy to do this? Would you expect your scheme to support your decision if you did?

I see your point, but to be fair that is hugely more dangerous than unsheathed cables buried in plaster.


The thing is, when I read this:

I being the person responsible for the Design, Construction, Inspection & Testing of the electrical installation (as indicated by my signature below), particulars of which are described above, having exercised reasonable skill and care when carrying out the Design, Construction, Inspection & Testing, hereby CERTIFY that the said work for which I have been responsible is to the best of my knowledge and belief in accordance with BS 7671:2008, amended to 2011 except for the departures, if any, detailed as follows.

I think it's talking about the work for which the person signing it was responsible, and certifying that the work he did complied with BS 7671. I can't see anywhere where it says that he's also certifying that the existing parts of the installation which he touched complied.

 

[securespark]

insulated or uninsulated singles?

Do you mean 'sheathed or unsheathed' (or 'single insulated' or 'double-insulated'/'single insulated and sheathed')? .. they would surely not have used bare conductors, no matter how incompetent they were!!

They could have done in the 1st Ed., providing they were placed out of reach.

 

[mfarrow]

Do you mean mechanical protection?

No I mean the application of one of the recognised methods of fault protection as per 7671. If you don't have at least one one of these methods then the (part) installation is unsafe. We all recognise not having CPCs where ADS is our chosen method as being dangerous but there is nothing in law to distinguish that situation as being any less safe than not having sheathing on cables/circuits where Double or Reinforced insulation is our chosen method.

What if you noticed that somehow but weren't doing work on the circuit? To what extent would you be unprepared to have anything to do with any of the installation?

I would feel obliged to mention it but if I'm not working on the circuit then I wouldn't consider it to be within the scope of work. If I was to work on the lighting circuit however and do what I described, the perception I would leave the customer with is that it was safer than before. Customers can also forget their own instructions, and if another electrician visited later all he'd see was a dangerous circuit rewired by, oh yeah mfarrow trading did that for me, and he may even convince the owner to complain to the scheme. That's not the kind of hassle you want.

I see your point, but to be fair that is hugely more dangerous than unsheathed cables buried in plaster.

In respect of it being immobile from the plaster then yes I'd agree. But it still lacks fault protection and neither 7671 nor any of the competent persons schemes recognises plaster as a means of providing Double or Reinforced insulation.

 

[JohnW2]

We all recognise not having CPCs where ADS is our chosen method as being dangerous ....

Well, you can't actually have ADS without a CPC. However, that aside, it doesn't seem to stop many electricians doing 'appropriate' work (e.g. replacing plastic switches/roses/light fittings with plastic) on a lighting circuit which has no CPCs - indeed, there is even 'official' guidance about doing such work.

...but there is nothing in law to distinguish that situation as being any less safe than not having sheathing on cables/circuits where Double or Reinforced insulation is our chosen method.

What you say is probably ('literally') true. However, we were talking about buried, inaccessible, cables (buried in plaster I think). In terms of common sense, do you really believe that having a PVC sheath on such cables would result in the installation being appreciably 'safer' ('less dangerous')?

If I was to work on the lighting circuit however and do what I described, the perception I would leave the customer with is that it was safer than before. Customers can also forget their own instructions ...

That is why one would annotate the documentation appropriately (and keep copies, and, if you wanted, send copies at the time to any relevant people/bodies!)

Kind Regards, John

 

[EFLImpudence]

I would be interested to know what the scheme/body would do with this information.