Cable Sizing

[tallpault]

How do you guys check your cable sizes,when your carrying out your pirs.I was struggling today with some di tails.Any help would be great.

 

[Andy™]

usually from experience, although i have had to measure the diameter of a strand to get CSA

 

[tallpault]

What you measure the size of a strand and then times it by how many?

 

[Apache]

What you measure the size of a strand and then times it by how many?

remember your triganometry, area of a circle is pi * radius squared (you have measured diameter)

assumuming you are measuring the conductor not the insulation

 

[Apache]

or to work backwards

radius = sqrt(area / PI)

so 25mm2 cable would = sqrt(25/3.14)

so 25mm2 cable has a radius of 2.82 or a diameter of 5.64mm

see?

 

[tallpault]

Does anyone know if there is a chart where you can measure the diameter of an insulated cable and it gives you the csa of a cable.If anybody had that would be the biz.

 

[Apache]

Does anyone know if there is a chart where you can measure the diameter of an insulated cable and it gives you the csa of a cable.If anybody had that would be the biz.

it would vary by manufacturer surly?

 

[Andy™]

or to work backwardsradius = sqrt(area / PI)

so 25mm2 cable would = sqrt(25/3.14)

so 25mm2 cable has a radius of 2.82 or a diameter of 5.64mm

see?

not quite patch - there is usually air in the spaces, so you would need to measure an individual strand and times that by number of strands for total CSA

 

[Andy™]

Does anyone know if there is a chart where you can measure the diameter of an insulated cable and it gives you the csa of a cable.If anybody had that would be the biz.

there are some rough measurements out there, but each manufacturer may use a different insulation/ other variables so it wouldnt really be reliable

 

[Apache]

not quite patch - there is usually air in the spaces, so you would need to measure an individual strand and times that by number of strands for total CSA

pah - would give you a fair idea

 

[Andy™]

pah - would give you a fair idea

probably a few mm

 

[Apache]

probably a few mm

 

[Andy™]

 

[green-hornet]

I do it by experiance, which most people do I think. You get used to what your looking at over time.

Like andyc says each cable manufacturer has different sheathing sizes.

If its really old cable then you get into the realms of the imperial sizes.

 

[WarrenG]

Likewise by experience but I have known some sparks carry small cuttings of cables around with them as a rough guide.

Gets a bit tricky with really old cable though.

 

[SPECIAL LOCATION]

or to work backwardsradius = sqrt(area / PI)

so 25mm2 cable would = sqrt(25/3.14)

so 25mm2 cable has a radius of 2.82 or a diameter of 5.64mm

see?

only if SOLID core!

probably a few mm

 

[SteveD90]

Hi Tallpault,

what I have had for many years is a collection of lugs from 1.5 to 300 mm on a large key ring which comes in handy especially on larger cables that you dont meet every day.The ones you want are non flared with parallel sides so you can also just hold up against the insulation to gauge it,s size when you cant try it on the end of the cable.