Steel Wire Armoured Electical Cable - How Can I Tell The Cable Guage/Size/Thickness?

[sessionsdenseflannels]

I have some SWA electrical cable that was left by the previous homeowner when we bought our house. There's about 15 metres of the cable and it's in decent condition, so I may want to use it or sell it. But I can't tell what the guage or thickness of the cable is. All that is printed on the exterior sheath is "Electric Cable 600/1000 V BS5467", "Basek Demes Kablo 3x4 (2017)", and "CE RoHS 1714806 24/05/2017". I've tried Googling all this and it hasn't turned up any useful information.

What I'd like to know, very simply, is whether the SWA cable is 1.5mm, 2.5mm, 4mm, 6mm guage etc.? How do I measure this?

I've attached photos of the cable and my very DIY attempts at measuring the cross-section with a steel ruler.

Any advice would be appreciated!

 

[binky]

3x4, 3off conductors at 4mm

 

[sessionsdenseflannels]

3x4, 3off conductors at 4mm

Thank you!

 

[apprentice87]

That cable is not even worth advertising.. Would be about £35 plus the vat brand new..

 

[BorisJ]

You cannot measure with a steel rule. You need a micrometer or dial gauge callipers to measure one strand diameter. Then use pi x dia squared divided by 4 to get the csa. Finally multiple by the number is strands.

 

[Andy™]

That cable is not even worth advertising.. Would be about £35 plus the vat brand new..

DIYer logic is a bit different

 

[john clark01]

You cannot measure with a steel rule. You need a micrometer or dial gauge callipers to measure one strand diameter. Then use pi x dia squared divided by 4 to get the csa. Finally multiple by the number is strands.

It tells you on the cable the size and the number of cores. Anyway who reuses second hand cable?

 

[roys]

It tells you on the cable the size and the number of cores. Anyway who reuses second hand cable?

Me me me, the last house I stayed in I used 20m of 3 core 6mm to feed my garage, it was 2nd hand used for 2 months to feed a site office, got job to disconnect it, why would I not reuse it as it was in perfect condition.
Reuse, reduce, recycle after all.

 

[Marvo]

Looking at the state of the copper conductor it looks like that cable was cut whilst it was live....

 

[binky]

Looking at the state of the copper conductor it looks like that cable was cut whilst it was live....


View attachment 15519

Suggests water/ damp has got into the ends to me.

 

[kerching]

Looks like it was cut with a JCB back hoe

 

[SPECIAL LOCATION]

It tells you on the cable the size and the number of cores. Anyway who reuses second hand cable?

But is it second-hand.. or just a left over unused offcut from a longer reel/drum?
The OP does not say the cable has been used??
and this cable may never have carried any electrical current in its lifetime!

I regularly use any and all, left-over offcuts rather than wasting the remains of part-used reels/drums..

Looking at the photo I would probably cut the exposed end off, 500mm ish' then recheck the condition of the conductors & armour to ensure no major damp / corrosion ingress issues with the steel armour?

At the end of the day providing it tests out ok, IR, Continuity of conductors etc.. why would you not use it???

Cable is no different to any other product, if it still has some working life left
and can be used safely only an inconsiderate polluter would not re-use it!

The OP's post suggests there is a 15m length of 3core 4mm..
So if you could get 10m or 12m of good quality, electrically safe, cable from this "off-cut"
I know of numerous domestic applications where this SWA could provide a supply to an outbuilding / shed / greenhouse.. etc..

I assume that if this piece of cable was already connected to a working installation, and tested out as satisfactory during an EICR you would not recommend it needed replacing?
So... in this day and age where we all need to be conserving energy and reducing waste why would you not use it??

Back to the original question:
Extra info for @sessionsdenseflannels as a price comparison a 10m length of 3-core 4.0mm SWA can be bought from Screwfix for £34.99
https://www.screwfix.com/p/prysmian-6943x-black-3-core-4mm-armoured-cable-10m-coil/94686

So this gives a rough bench mark of what you may hope to get from E-bay sale.