My house is a 1950s 2 story semi. I am connecting one fluorescent downstairs kitchen light in parallel with another fluorescent, without taking up any more upstairs floorboards.
I have found a mass of single core PVC wires.
Does anyone remember what colours were used in the 1950s lights for wiring, so that I can cut the right wires?
Red for live, black for neutral - exactly the same as until quite recently.
1950's though would probably be VIR - rubber insulation which becomes very brittle covered by a waxed woven cotton for protection, or rubber with a tough rubber overlay for protection. So the VIR would look a red/brown colour, rather than red - all well overdue for replacement.
Red and black - same as up to recently.
On Sun, 17 Dec 2006 12:51:35 +0000 someone who may be Dave Fawthrop wrote this:-
You should find a terminal block in the current fitting, which has live neutral and earth terminals. Don't cut anything, just run a new cable from this to the new fitting.
You have informed John Prescott I take it.
Red is the equivalent of Brown and Black is now Blue. Earth was a plain green and is now green and yellow.
Go f*ck yourself.
Weatherlawyer presented the following explanation :
Apart from the fact that it would be unlikely to have been wired with an earth, those which were provided with one were just bare copper wire.
On Sun, 17 Dec 2006 13:54:53 GMT someone who may be Harry Bloomfield wrote this:-
Or alternatively the earth connection was made via the screws from the conduit.
PVC was in use by 1955, but not exclusively so -- rubber was still being used too. There may be no earth in 1950's lighting circuits -- it was optional. If there is no earth, you can only use class II (double insulated) light fittings.
David Hansen presented the following explanation :
... and the (likely) grip conduit joints will be so rusted that it would no longer be safe to rely upon it for earthing purposes.
There is a problem with half a century old rubber wiring. Its often in such bad condition than any disturbance is liable to cause shorts, fusenpoppen, shock or fire. In short, leave it well alone. The solution is most likely to open the existing fl light and connect it up there, making sure you dont run the new wire past the hot choke.
There is also the question of earth, the new fitting should be earthed, assuming its metal cased. To achieve this you can rewire your lighting cct if it has no earth. Borrowing an earth from somewhere else is sometimes done, but this is not regs compliant, and there are reasons why, so you should not do it. In short theres not much chance of you being able to do it to modern safety standards without rewiring. But if you choose to do so anyway, at least dont disturb the old rubber wiring, thats where the biggest danger lies.
NT
How does that apply to pvc wiring?
It doesnt apply to pvc, which is normally in healthy condition at that age. Ditto with ashathene, which looks like pvc.
NT
I never saw domestic house wiring in PVC until the '60s. Although it was common for some types of flex. Perhaps Aberdeen was rather conservative. ;-)
=============================== It was certainly available in the early 1950s but I think it may have been available as separate single cables rather than sheathed.
There was one of those 'crazes' in the mid 1950s for using PVC covered wire for making bangles, bracelets, fancy belts and even woggles.
Cic.
|Harry Bloomfield wrote: |> David Hansen presented the following explanation : |> > On Sun, 17 Dec 2006 13:54:53 GMT someone who may be Harry Bloomfield |> > wrote this:- | |> >> Apart from the fact that it would be unlikely to have been wired with |> >> an earth, those which were provided with one were just bare copper |> >> wire. | |> > Or alternatively the earth connection was made via the screws from |> > the conduit.
We just had a new combi boiler fitted and they did a good job of earths.
|> ... and the (likely) grip conduit joints will be so rusted that it |> would no longer be safe to rely upon it for earthing purposes. | |There is a problem with half a century old rubber wiring.
Its definitely PVC like the sheds sell now.
That reminded me of;
Poken Verboten
Achtung alles lookenpeepers. Das machine is nicht fur gefingerpoken und mitten grabben, Das easy schappen der springenwerk, blowen fusen und poppen corken mit spitzen sparken. Is nicht fur gewerken by das dumkopfen. Das rubbernecken sightseeren keep hands in das pockets, relaxen und watch das blinken-lights.
youre lucky. Will still be various safety issue, but not the cable itself, which is the worst of all on most old installs.
NT
And even if you think they look OK, pin-grip and plain slip joints in conduit are specifically disallowed in the regs nowadays [543-03-06].
The transition period from TRS to PVC for twin and twin-and-earth cables was quite long.
Someone[1] posted the following list of dates on the IET wiring regs forum not too long ago:
Try these approximate dates:
Lead sheathed cables: pre-1948.
Tough rubber (TRS): 1945-1962.
Capothene and Ashothene Sheathed Cables: 1952-1960.
PVC/PVC cables without cpc (lighting): 1955-1966.
Imperial cables PVC: 1955-1971.
2.5mm PVC/PVC with 1mm cpc: 1971-1981.Black earth conductors: pre-1966.
Green protective sleeving: pre-1966.
Absence of main equipotential bonding conductors: pre-1966.
2.5mm main equipotential bonding conductors - small installations: 1971-1972.6mm main equipotential bonding conductors - small installations: 1966-1983.
10mm main equipotential bonding conductors - small installations: post-1983.Twin twisted flexible cords: pre-1977.
Fault voltage operated circuit breakers: pre-1981.
Accessories mounted on wooden blocks: pre-1966.
Non-13A socket-outlets pre-1955.
Double-pole fused switchgear on AC installations: pre-1955.
Others might may have other recollections. I appreciate that some things were being used some time after the dates e.g. 15amp sockets.
[1] Original source here:
Could be: I was referring to TW&E or Twin sheathed.
PVC flex was certainly common. Usually without a sheath, too. Trying to remember the name of the black and red twisted stuff.
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