Is there a Tool for measuring the CSA of wire

[STI]

Just wondered if such a thing exists.
Just curious as the CSA is such an important element when checking if the right wire has been used for the right circuit.Looking at wires i would really struggle to tell the difference between a 6 and a 10 mm CSA and even worse for a 1mm or 1.5mm.

 

[flameport]

Something like this:

will measure the diameter of the wire, from that it's a simple matter to calculate the csa.
Or just make up a short list of the various sizes: diameter / csa.

 

[properleckie]

piece of metal with relevent holes drilled along one edge?

or long thin vee notch cut in metal with scribed lines at measured widths.

maybe should make and sell....

 

[STI]

thanks. I looked on the internet before i posted this question and i came across a few sites which gave what appeared to be horrendous calcs to get the CSA from the diameter. So i thought someone must have invented a tool for use by lazy or thick s*ds like me that you can just stick the wire in clamp around it and hey presto the CSA is given. Looks like i will have to get the old brain trainer out again.

 

[ban-all-sheds]

thanks. I looked on the internet before i posted this question and i came across a few sites which gave what appeared to be horrendous calcs to get the CSA from the diameter.

I'm not trying to put you down, but if you think that Pi x r² is a horrendous calculation then I'm afraid electrical work is not for you.

 

[ericmark]

Yellow 6mm ferrules do not fit 10mm cable that's easy.
Between 1mm and 1.5mm little more of a problem area = pi R sq so 0.636619772 to 0.779696801 is pretty close and burrs when snipping can easy make 1mm look like 1.5mm with no go gauges but vernier scales are enough does not really need a micrometer. Some callipers have digital scales on now and Lidi and Aldi do sell them form time to time. Although some practice with the amount a red ferrule waggles on the wire is normally good enough.

The real problem is where writing can't be seen on cable how does one know if 70 deg C or 90 deg C? So without reading the markings pure size does not help much. So worrying between one size of cable is really a little pointless.

 

[conny]

Contact wiring manufacturers, such as Lewcos, and ask for a wire tables booklet.

This tells you the csa of a wire when you look up the diameter and also gives a lot of other valuable information.

Experience will eventually teach you the difference even between 1.00mm and 1.50mm

 

[TicklyT]

A drill gauge may be useful :-

Find which hole each size conductor fits, and mark the CSA on the plate.

 

[GaryMo]

Just wondered if such a thing exists.
Just curious as the CSA is such an important element when checking if the right wire has been used for the right circuit.Looking at wires i would really struggle to tell the difference between a 6 and a 10 mm CSA and even worse for a 1mm or 1.5mm.

Just use a digital vernier as mentioned and apply the following calculation:

CSA = (π x d²)/4

π = 3.14159
d = diameter measured with vernier in mm

To find the diameter from a known CSA:

d = √ ((CSA x 4)/&#960

 

[Aragorn84]

You can buy digital vernier calipers from ebay for less than a tenner.

Just dont leave them sitting on the scuttle panel of the car your working on for a week in the rain, they dont like that.

 

[BS3036]

...digital vernier calipers..

One of the most useful tools I have. One essential use is for sorting drill bits back into the right holes in the box.

 

[STI]

Thanks everyone for the help.

Ban all sheds, now i know this is the formula then you are quite correct it is simple.

The calculation i saw on the net was (apologies i do not have the scientific keyboard set up.)

Calculation of the cross section A, entering the diameter d:

A= r2.pi=d2.pi/4~0.784.d2

Perhaps my use of the word horrendous was a little extreme and given a few minutes yes i am capable of the calculation above but compared with sticking a piece of wire in a device, if it existed, to get the same answer, i would choose the device every time.

Trade or specialist Terminolgy can be confusing to anyone outside of a trade. When i fist sold computers in the mid eighties me and my team of highly specialised people would present to potential buyers and we would talk about MTBF, MIPS, MEGABITS with all sorts of TLA's thrown in for good measure. We knew exactly what we meant but suprise suprise our audience at that time who where the endusers of the product, hadnt got a clue what we were talking about.
Was this their fault, absolutely not. We were the ones in the wrong by using trade terminology to non trade buyers and not appreciating they probably needed to be helped and educated, in the nicest sense, to understand the terminology in their terms.

The point is they wanted to learn. The same applies on this excellent forum, most posters want to learn and be safe in what they do but they need the help of the knowledgable people on this forum to do that. Yes I and maybe others may not have understood that actually the CSA of a wire is in non trade terms is the area of a circle, or that Domestic Part P is a set of guidelines and not legislation but its not because we are thick its because at the point of asking the question we didnt know.

 

[mattylad]

Does it not say the size on the wire?

 

[PrenticeBoyofDerry]

http://www.alibaba.com/product-tp/226241258/Wire_Gauges.html
also on amazon uk

 

[ban-all-sheds]

The calculation i saw on the net was (apologies i do not have the scientific keyboard set up.)

Calculation of the cross section A, entering the diameter d:

A= r2.pi=d2.pi/4~0.784.d2

That's just showing you how to arrive at a way of working it out without having to first divide the diameter by 2 to get the radius. You don't have to do the whole thing, just the last bit, which is a simple calculation.

A = Pi x r²

If you have the diameter, and don't want to calculate the radius, you have to account for the fact that d² = r² x 4, so your A = Pi x r² has to become

A= Pi x d²/4

Pi ≈ 3.14159, so Pi/4 ≈ 0.7854.

So A = 0.7854 x d²

Perhaps my use of the word horrendous was a little extreme and given a few minutes yes i am capable of the calculation above but compared with sticking a piece of wire in a device, if it existed, to get the same answer, i would choose the device every time.

Actually, as cables come in only a few standard sizes (in a domestic context), all you need to do is to draw up a little table of diameters & CSAs. A cheapo 1 decimal place vernier caliper will be precise enough to tell you which of the standard sizes you must have.

We were the ones in the wrong by using trade terminology to non trade buyers and not appreciating they probably needed to be helped and educated, in the nicest sense, to understand the terminology in their terms.

I wouldn't have classed "CSA" as a trade term - is it not the standard abbreviation for cross-sectional area?

Yes I and maybe others may not have understood that actually the CSA of a wire is in non trade terms is the area of a circle,

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

or that Domestic Part P is a set of guidelines and not legislation

Part P is not a set of guidelines, it is one of the parts of the Building Regulations, i.e. it is legislation.