Is there a Tool for measuring the CSA of wire

[securespark]

as conductors have a circular cross-section, their CSA must be the area of a circle?

I appreciate you are talking about domestic cables here, but not all have a circular cross-section.

 

[empip]

Use this to tabulate ??
Click here Then edit the '02.5' to suite known CSA read resultant equivalent diam... in mm
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[stunlawless]

Morning everyone,

Calcs get a bit involved when cables are stranded. if there are 7 strands, the cable assumes a hexagon layout. By measuring either the diameter of a single strand, the major diameter (across the points of the hex) or the minor diameter (across the flats) you can get the CSA from this table:

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• stunlawless
• 16 Nov 2009
• 1

Be careful when measuring the hex diameters - it can distort and give a false reading. for that reason, I prefer to measure a single strand, but this isn't always possible without dismantling a joint.

Hope this helps, David

Edited for spelling

 

[MartinFa]

Good table, stunlawless - I wish I'd found it before constructing my own from experience & measurements!

I'd also add that I've come across 3 strand 1.5mm^2 twin & earth cable with solid 1.0mm^2 cpc. The strand diameter is 0.8mm.

With the prevalence of smartphones and downloadable apps, I've created a simple Excel spreadsheet you can use on a PC or smartphone. As long as you have a vernier caliper for the measuements, just tap in the strand or conductor diameter, tne number of strands, and it'll give you the CSA.

You can download it from my website here.

Hope it helps

 

[stunlawless]

Cheers Martin.

I never got round to the live app, but I'm glad someone has.

Regards, David

 

[Stoday]

I'd also add that I've come across 3 strand 1.5mm^2 twin & earth cable with solid 1.0mm^2 cpc. The strand diameter is 0.8mm.

I think you really came across 3X.029 with a 1X.044 cpc.

I'm surprised everyone seems to remember pi as 3.14159 rather than the ratio 355/113, which is more accurate.

 

[stunlawless]

Stoday, how many dp do you need ?

Both are the same to 5dp, which is 3 more than the accuracy needed for every day work.

Even the best calipers or micrometers (outside of a calibration lab) won't give more than 2dp !

Regards, David

Ps I was taught to use 22/7, which is 3.142 to 3dp - good enoug for most purposes.

 

[MartinFa]

I'd also add that I've come across 3 strand 1.5mm^2 twin & earth cable with solid 1.0mm^2 cpc. The strand diameter is 0.8mm.

I think you really came across 3X.029 with a 1X.044 cpc.

I'm surprised everyone seems to remember pi as 3.14159 rather than the ratio 355/113, which is more accurate.

I'm assuming those measurements are in old money? You may well be right. I measured the strands as being 0.79mm dia, but it's not difficult to be inaccurate at that level of resolution with hard steel jaws on soft copper!

 

[EFLImpudence]

I'm assuming everyone on here has a computer.

Windows calculator has pi to 31 dp.

 

[bernardgreen]

Windows calculator has pi to 31 dp.

Useful when planning a 6 month inter planetary journey when an error of a mile after a couple of million miles travelled is too much error.

But for most work 22 / 7 ( = 3.1428571428571428571428571428571 ) makes long hand calculation easy with an "error" of 0.04 %

 

[Stoday]

I just find it easier to remember and use the ratio of two integers rather than a decimal to express a constant. It may be worth noting that for a given number of digits, both methods have the same accuracy. Thus the accuracy of 22/7 is in the same order as 3.14 and 355/113 as 3.14159.

But then, I was brought up in the (now forgotten) slide-rule age, the age before the electronic digital calculator age.

 

[bernardgreen]

But then, I was brought up in the (now forgotten) slide-rule age

I remember them, but now I can't remember where I put mine.

 

[JohnW2]

I just find it easier to remember and use the ratio of two integers rather than a decimal to express a constant. It may be worth noting that for a given number of digits, both methods have the same accuracy. Thus the accuracy of 22/7 is in the same order as 3.14 and 355/113 as 3.14159.

This is starting to remind me of some lectures on number theory which reside somewhere in my very dusty memory! Might I suggest that, in contexts such as the one of this thread, taking pi as 3 (or maybe 3.1) is probably quite adequate?!

But then, I was brought up in the (now forgotten) slide-rule age, the age before the electronic digital calculator age.

So was I (and I still have several slide rules, including a cylindrical one capable of 4 digit accuracy) - but there was no need to fiddle around with these fractions - pi was almost unvariably marked on the scale of the slide rule.

Kind Regards, John.

 

[ban-all-sheds]

If it was a good one, and you find it, they can go for good money to collectors.

 

[JohnW2]

If it was a good one, and you find it, they can go for good money to collectors.

Are you referring to this:

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• JohnW2
• 18 May 2011
• 2

If so, I suspect my offspring will be inheriting it (along with lots of other ancient rubbish!).

Kind Regards, John.