For the electrical historians-How old is this wire?

Orionaut

Orionaut

Orionaut

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The wire is a single copper core around 0.9mm diameter (Though will be pre-metric) with a round red/brown/green (As I am RG blind it could be any of those) rubber insulator further encased in a black (Or very dark brown etc) rubber outer covering of a hexagonal overall cross section around 5.5mm across the flats.

I am guessing at least 80 years old.

I would not expect this property to have been on mains electricity at this time though it may well have had a phone line or even its own generator/light plant.

Can anybody identify what this wire might have been for (I am thinking Phone as most likely, though it could have been used with a light plant) and approximately how old it might be, particularly regarding minimum age.

Ta!
 
BigBoy said:
Sounds like old VIR (Vulcanised Indian Rubber) cable. Probably bell wire thin two core? What we now class as bell wire or audio cable (for non audio snobs) was commonly used around the home in the early days of electricity for every outlet and light bulb

something like this? http://wiki.diyfaq.org.uk/index.php/Historic_Mains_Cables#VIR.2FVRI
Click to expand...

Could be, my cable however has a double layer of insulation, An inner red one with an outer black sheith.

I have only found one short strand thus far, (And the insulation is actually in very good condition, no cracking or perishing) but I can establish a sort of time line since it was trapped behind some rafters that had been installed to support a lath and plaster ceiling which in turn was constructed using lime plaster with hair reinforcement. Lime plaster had largely fallen out of use in new construction by the 1920's though use might have persisted for rather longer in remoter rural areas, (Which this is. My nearest supermarket is nearly 20 miles away, )

I do not know when this part of the country was connected to the grid, mains electricity might have been available from the 1920's though telephones would have been available much earlier.

Places like this might well however have relied on different methods for electricity supply

This sort of machinary was used well into the 1950's in remoter rural locations (Though there is no evidence that it was ever used here)


(The Start-o-Matic system was quite clever, It suppled all circuits with a low voltage DC supply when the generator was not running, if any switch was closed, the control box would detect this and automatically start the engine. When the switch was opened the engine would stop saving fuel. Of course, it took a couple of seconds (Well, 20-30 :D ) to get up to speed so lights wouldn't come on immediatly, but it was a big improvement with faffing around with an oil lamp. Other Lister systems used battery banks to provide power for lighting, but their operation was not automatic and the owner would have to actively switch on the generator from time to time to ensure the battery bank was kept charged)
 
It's part of my job to identify this type of cable and report on it as it's now classes as high risk and danger to life. (I work mains supply). I'm also to remove as much as possible of it without disturbing what I can't remove. I'm 99% sure it's VIR, it comes in single and double insulated forms, the cross hatching is usually the weave of the fabric visible through the rubber coating.

You would be surprised how much of it is out there and still in use. A large portion of the mains network is still lead cased paper wrapped and impregnated with tar :eek:
 
PILC cables are bulletproof :) Don't move them and stick and Insulation Resistance test down them every now and again and they'll outlive me.

VIR cables on the other hand.........definate fire hazard, even an insulation resistance test can damage them if they're really brittle and degraded. Replace immediately.
 
sounds like what we found in our place when we just had it rewired. Our place is 1930s built and that section of wiring so far as we could tell was the oldest stuff, though we can't guarantee it is original wiring from the 1930s. The 1990s alterations used white-sleeved dual core and last year's stuff was all grey sleeved dual core. There was some basic building work (lean-to extension) in the late 1960s that got replaced in the 80s so it might be from the 60s but that's as much as I can discern from the limited info I've got here.
 
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