does anyone have problems determining the size of cables between 4mm2 and 6mm2?
this can be a seriouse mistake if misjudged.

Also does anyone use a micrometre to calculate the size of cable using 3.14 * radius squared?

i have tried this method and cant seem to determine the true sizes both on stranded and solid.

James,
Not as a rule, any Electrician worthy of the name would know that a 4mm2 wire comprises 7 wires each being 0.85mm in diameter.
A 6mm2 wire comprises 7 wires having a diameter of 1.04mm.
Personally I've used a micrometer, to gauge Commutators and to gauge the gap on a set of HV reclosers, but if a guy bought a set of them out to measure wire sizes on a job site?.
It's good, quality Control!.

I must admit that at a quick glance it's much harder to distinguish between 4 and 6mm than between, say, 1.5 and 2.5mm.

Actually, it wouldn't be a bad idea if the cables were marked somewhat more clearly as to conductor size.

"...any Electrician worthy of the name would know..." Aw...steady on!

Unless you are opening an accessory or looking at the conductors you can't see how many strands there are...

Personally I haven't been caught out yet, but I can quite see how someone trying to ID whether an isolated sample in a bundle is 4 mil or 6 mil might struggle; particularly as different manufacturers use differing thicknesses of outer sheath. I go with Paul here - a better indication on the sheath would not go amiss.

As for a quick ID - not always that easy.

If you find it hard to tell the difference between two different sized cables, your not worthy of the title 'electrician'?
now things are getting a bit silly.

i have known many people to misjudge cable sizes, this was only a question trumphy i did not ask to be insulted.

thanks for your reply/honesty pauluk,uksparky

Suggestion: The manufacturers could print/stamp the size as a 6 with a trailing square on the individual cores with regular intervals. (American cables would have a #10 )

The distance between the markings should be relatively short and on both sides of the core. (I know a circle only has one side, but you know what I mean )

Otherwise, the American concept of coulour coding the cable sheat is not bad. On European NYM, you could colour code the filler instead of the sheat. (White - 1.5 mm2, Yellow - 2.5 mm2, Orange - 4 mm2)

'S ok James

Without questions we gain nothing...

Whoa!,
Sorry guys.
James, I never intended to come across in such a condescending fashion, this was not my intention at all.
I apologise for my comments.
Oddly enough, our TPS cables are marked as to thier size and the number of cores and the types of cores (ie:2C+E or 3C).
Also they have a metre-marking on them, to identify, the amount remaining on your reel.
This comes in handy for stock control and charging out cable lengths used on jobs.

during my apprentiship using a micrometre to size up cable was one of the things to be carried out as part of your portfolio.A while back now though.
ive noticed some brands of ammoured cables also don't have the size/amount of cores.

colour code would not be a bad idea.

ps no apology needed,all's forgotten

[This message has been edited by james S (edited 11-09-2004).]

Now that I could really get used to!!

What a sensible plan.

That does sound a handy idea. Are they just numbered throughout a whole run of cable, or are the measured for each individual drum? The latter would be easiest to see how much is left, but I can how it would make cutting and winding reels more time-consuming as you'd need to line up the marks.

How about dual-scale markings like tape measures -- Meters one side, feet on the other?

Jeez Paul...steady on!! One cool idea at a time if you please!!

LOL

An overly cool tool:
http://www2.catalognavigator.com/st...etid=spec&forward=1&backtoname=#

If you look closely at the picture, you see that the dial has two hands. The black hand is the measurement in inches, 0.1" per revolution. The red hand is the measurement in mm, I think 2mm per revolution.


-Jon

I've two 100m long reels of 6mm2 here under my bed, and it has "PIRELLI CABLES 1993 BASEC 6mm2 6242Y BS6004" embossed every half metre down the cable. No length markers though (like you get on polyethylene water pipe).
Gideon.