1mm single around lighting circuit

[Skys]

Just carrying out a EICR . Lightning circuit has a separate what looks to be 1mm single around all points. This has no mechanical protection so should be 4mm. Coding this has a C3. installation is still safe for continued use. Bit I’m struggling with is what section the C3 should fall under. If any? Any help?

 

[DPG]

Is it a single or a sheathed single? In the 1970s it was fairly common to use sheathed singles, the line one having an earth conductor, sort of 'single and earth'.

 

[Pete999]

Is it a single or a sheathed single? In the 1970s it was fairly common to use sheathed singles, the line one having an earth conductor, sort of 'single and earth'.

Singles with cpc were common in the 70s both Red and Black.

 

[Risteard]

Just carrying out a EICR . Lightning circuit has a separate what looks to be 1mm single around all points. This has no mechanical protection so should be 4mm. Coding this has a C3. installation is still safe for continued use. Bit I’m struggling with is what section the C3 should fall under. If any? Any help?

When you state that "this has no mechanical protection so should be 4mm" (squared) do you mean that this is the cpc? If it is a live conductor then regardless of cross-sectional area it is not permitted to be lacking mechanical protection, e.g. a sheath. A non-sheathed cable used as a protective conductor must have a minimum cross-sectional area of 4mm^2 if not in containment etc.
[automerge]1579620806[/automerge]

Is it a single or a sheathed single? In the 1970s it was fairly common to use sheathed singles, the line one having an earth conductor, sort of 'single and earth'.

They're still common here. Although brown isn't necessarily brown & Earth. You can get PVC/PVC brown (no cpc) as well. And you can also get blue & Earth as well as PVC/PVC blue.

 

[Skys]

it’s single red with sheath, single black with sheath. Then a 1mm cpc solid green around all the accessories. The spec here for councils is still to wire in singles and cpc sheathed Both live and neutral must contain the cpc. In wholesalers we just ask for singles and earth.

 

[Pete999]

it’s single red with sheath, single black with sheath. Then a 1mm cpc solid green around all the accessories. The spec here for councils is still to wire in singles and cpc sheathed Both live and neutral must contain the cpc. In wholesalers we just ask for singles and earth.

Then you asked for the wrong type of cable!! Singles WITH cpc would have made them think as well as your outfit

 

[Andy78]

it’s single red with sheath, single black with sheath. Then a 1mm cpc solid green around all the accessories. The spec here for councils is still to wire in singles and cpc sheathed Both live and neutral must contain the cpc. In wholesalers we just ask for singles and earth.

There is no regulation I know of that requires a cpc in sheathed cables, so no code there. Unless your eicr is being carried out to a different spec.
Cpc is undersized if unsheathed though by the sounds of it.

 

[Pete999]

There is no regulation I know of that requires a cpc in sheathed cables, so no code there. Unless your eicr is being carried out to a different spec.
Cpc is undersized if unsheathed though by the sounds of it.

Some thing to do with unprotected cpcs should be protected, conduit or trunking or mim 4mm I believe, and for the OP you can get single cable sheathed and including a cpc.

 

[Skys]

Yes we have to wire with the singles combined with cpc that’s all we use for lighting circuits that’s the spec. My question is to the separate cpc not having mechanical protection. I was always taught this should be 4mm and if protected 2.5mm. I have made a note in summary of the condition of the installation. Just unsure of what section if any to code it in inspection schedule.

 

[Pete999]

Yes we have to wire with the singles combined with cpc that’s all we use for lighting circuits that’s the spec. My question is to the separate cpc not having mechanical protection. I was always taught this should be 4mm and if protected 2.5mm. I have made a note in summary of the condition of the installation. Just unsure of what section if any to code it in inspection schedule.

Why is it the spec to wire in singles seem very outdated? but not against the BS, are these circuits wired in Steele conduit and trunking, and the installers don't know how to utilise the containment as the cpc?

 

[westward10]

See Regulation 543.1.1

 

[ipf]

Sounds like whoever did the installation didn't have any single and earth and so, as a result, wired in separate singles. Bad news.
Edit. Never seen any double insulated g/y single. Maybe a case for it?

 

[Skys]

Why is it the spec to wire in singles seem very outdated? but not against the BS, are these circuits wired in Steele conduit and trunking, and the installers don't know how to utilise the containment as the cpc?

Just the local councils spec. No steel conduit or containment just the singles and earth. Clipped direct to joists and oval tube plastic drops to accessories on walls. We just get the specs that there electrical design team issue.