What do you use to measure the csa of cables?

[DNS1]

Calipers? One of those cards with holes in? Or something else?

I know in the end I'll get to tell what is what by sight and feel but need something to help me in the meantime, especially with larger live conductors and earth bonding etc

 

[Snapester]

The writing on the side if there is any, but mainly i can tell by sight. I dont have time to measure.

 

[cdavies33]

My eyes!

 

[DNS1]

And for someone new to the game?

 

[telectrix]

build up a collection of offcuts, label them and use them for comparison.

 

[Knobhead]

I made a card that hung in the workshop with a sample of each size from 1mm through to 95mm. Easy for an apprentice to compare.

Other than that the weight per meter.

 

[SirKit Breaker]

Dont forget, the cross sectional area is the CSA of the copper bit, not the insulation. A tape measure will suffice for measuring. You will soon get to be able to identify by sight.

Cheers............Howard

 

[DNS1]

Cheers guys

 

[PC Electrics]

If you are doing domestic work (or work in other properties wired pre 70s) then you'll need a vernier caliper to measure the diameter of strands. The difference between 7/029 and 7/036 strand diameter is just 0.17mm. I defy you to tell by eye.

 

[i=p/u]

tape measure is good awnser to this question for those begining..

 

[DNS1]

funny how i got banned probably because of this member, apparently too good for the 2330 and two weeks later he admits he can't size cable by sight?!

Do what tele said if you lug them you could hang them on a keyring???

Why do you have such a problem with me peterdaniels?

I didn't make you be abusive to people. You did that yourself.

Oh and by the way, I did not say I'm too good for the 2330 as you are well aware.

 

[Knobhead]

For any one interested to tell the CSA by weight.

SG of copper = 8930KG per M³

So the weight per meter = CSA/1,000*8930

CSA MM Gm per M
[TABLE="width: 135"]
[TR]
[TD]1
[/TD]
[TD]8.93
[/TD]
[/TR]
[TR]
[TD]1.5
[/TD]
[TD]13.40
[/TD]
[/TR]
[TR]
[TD]2.5
[/TD]
[TD]22.33
[/TD]
[/TR]
[TR]
[TD]4
[/TD]
[TD]35.72
[/TD]
[/TR]
[TR]
[TD]6
[/TD]
[TD]53.58
[/TD]
[/TR]
[TR]
[TD]10
[/TD]
[TD]89.30
[/TD]
[/TR]
[TR]
[TD]16
[/TD]
[TD]142.88
[/TD]
[/TR]
[TR]
[TD]25
[/TD]
[TD]223.25
[/TD]
[/TR]
[TR]
[TD]35
[/TD]
[TD]312.55
[/TD]
[/TR]
[TR]
[TD]50
[/TD]
[TD]446.50
[/TD]
[/TR]
[TR]
[TD]70
[/TD]
[TD]625.10
[/TD]
[/TR]
[TR]
[TD]95
[/TD]
[TD]848.35
[/TD]
[/TR]
[TR]
[TD]120
[/TD]
[TD]1,071.60
[/TD]
[/TR]
[TR]
[TD]150
[/TD]
[TD]1,339.50
[/TD]
[/TR]
[TR]
[TD]195
[/TD]
[TD]1,741.35
[/TD]
[/TR]
[TR]
[TD]240
[/TD]
[TD]2,143.20
[/TD]
[/TR]
[TR]
[TD]300
[/TD]
[TD]2,679.00
[/TD]
[/TR]
[/TABLE]

Don’t forget this is the stripped weight of copper. (Good guide for weigh ins)!

For aluminium

SG of aluminium = 2560KG per M³

So the weight per meter = CSA/1,000*2560

CSA MM Gm per M
[TABLE="width: 129"]
[TR]
[TD][TABLE="width: 128"]
[TR]
[TD]1
[/TD]
[TD]2.56
[/TD]
[/TR]
[TR]
[TD]1.5
[/TD]
[TD]3.84
[/TD]
[/TR]
[TR]
[TD]2.5
[/TD]
[TD]6.40
[/TD]
[/TR]
[TR]
[TD]4
[/TD]
[TD]10.24
[/TD]
[/TR]
[TR]
[TD]6
[/TD]
[TD]15.36
[/TD]
[/TR]
[TR]
[TD]10
[/TD]
[TD]25.60
[/TD]
[/TR]
[TR]
[TD]16
[/TD]
[TD]40.96
[/TD]
[/TR]
[TR]
[TD]25
[/TD]
[TD]64.00
[/TD]
[/TR]
[TR]
[TD]35
[/TD]
[TD]89.60
[/TD]
[/TR]
[TR]
[TD]50
[/TD]
[TD]128.00
[/TD]
[/TR]
[TR]
[TD]70
[/TD]
[TD]179.20
[/TD]
[/TR]
[TR]
[TD]95
[/TD]
[TD]243.20
[/TD]
[/TR]
[TR]
[TD]120
[/TD]
[TD]307.20
[/TD]
[/TR]
[TR]
[TD]150
[/TD]
[TD]384.00
[/TD]
[/TR]
[TR]
[TD]195
[/TD]
[TD]499.20
[/TD]
[/TR]
[TR]
[TD]240
[/TD]
[TD]614.40
[/TD]
[/TR]
[TR]
[TD]300
[/TD]
[TD]768.00
[/TD]
[/TR]
[/TABLE]

[/TD]
[/TR]
[/TABLE]

I’ve been lucky, everywhere I’ve worked had analytical labs. Access to accurate scales wasn’t a problem.

 

[Silly Sausage]

I made a card that hung in the workshop with a sample of each size from 1mm through to 95mm. Easy for an apprentice to compare.

Other than that the weight per meter.

Now that's the advice of a Pik.....

Samples or holey plate, but usually 'educated' guesses.

 

[needasparks]

Now that's the advice of a Pik.....

Samples or holey plate, but usually 'educated' guesses.

You can't call our tinker tony (TT) a pik.....

 

[Knobhead]

Wouldn't be the first time :disguise:

 

[mickys86]

funny how i got banned probably because of this member, apparently too good for the 2330 and two weeks later he admits he can't size cable by sight?!

Do what tele said if you lug them you could hang them on a keyring???

Keyring sounds cool..... Can ya make me one? Make it easier to find my keys!!

 

[Strima]

I stab my finger with the end of the cable, after safe isolation is carried out just to be safe. The greater the volume of blood, the greater the CSA. I start feeling a little light headed over 16mm...

 

[Golden_Boy]

If you are doing domestic work (or work in other properties wired pre 70s) then you'll need a vernier caliper to measure the diameter of strands. The difference between 7/029 and 7/036 strand diameter is just 0.17mm. I defy you to tell by eye.

Yep vernier calipers then Pi r squared.

 

[the pict]

Plastic caliper about 6 quid can remeber where I got it if your not sure guesiing is a poor option
Pict

 

[Knobhead]

Yep vernier calipers then Pi r squared.

Think you’ll find it’s a bit more than πR²

To convert imperial to metric

Given 1²inch = 645.16²mm

(((π/4)*Core²)*Strands)*645.16 = metric equivalent

So say 7/.064
(((π/4)*0.064²)*7)*645.16 = metric equivalent
((0.7853*0.0040)*7)*645.16 = 14.523mm

 

[ipf]

With all the time it's taking you may as well measure the length and resistance and work it out from the OSG table (I don't think).

 

[ezzzekiel]

dosent matter just stick anything in sure it will be fine

 

[Golden_Boy]

Think you’ll find it’s a bit more than πR²

To convert imperial to metric

Given 1²inch = 645.16²mm

(((π/4)*Core²)*Strands)*645.16 = metric equivalent

So say 7/.064
(((π/4)*0.064²)*7)*645.16 = metric equivalent
((0.7853*0.0040)*7)*645.16 = 14.523mm

Measure DIAMETER in prefered units then divide by 2 then use πR²

 

[SKY]

I'm normally ok to tell by sight with sizes from 1.5 - 25mm.
I find that older cable has thicker insulation than the cable of today and sometime I find telling the difference between 4mm old cable and 6mm new (from a quick look).

I think that BASEC sould make it compusory that cable is marked every 12" or so. (some already are but many do not).

 

[Knobhead]

Measure DIAMETER in prefered units then divide by 2 then use πR²

So what about the air gaps between the strands.

Try using maths and physics, but don't try to beat me at it.

 

[Golden_Boy]

So what about the air gaps between the strands.

Try using maths and physics, but don't try to beat me at it.

Thats for singe strands NOT multistranded { I knew that degree would come in handy }

 

[Knobhead]

While doing your degree did you come across single strand IMPERIAL cable?

 

[Engineer54]

As i remember. 1/044 was quite popular in the very early days!! lol!!

 

[johnboy6083]

Finding the CSA of each strand in a larger shaped conductor would be nearly impossible I'd say, due to the fact that they are not round. Aloe cable sizes are not actual CSA's, but nominal CSA, based on current carrying capacity. This means that there could be slight discrepancies between manufacturers. I don't know how much you could allow for error and still measure, but maybe there is a rule of thumb.

 

[growler]

my 3 year old knows her csa off by heart clever girl

 

[La Poste]

Interesting thread, I have a seven stranded conductor I would like to know what the current carrying capacity is and have yet a find a really good method of finding out.

The air gaps in between the conductors comment has put me off the idea of using my vernier but I don't have a metre to weigh.

Maybe I should buy some really accurate scales and weight 5 CM because that's all the spare I have.

 

[Golden_Boy]

While doing your degree did you come across single strand IMPERIAL cable?

No I didnt as the subject matter I studied had no connection (sic ) to electrics at all..The maths comes in handy at times though especially integration !!

 

[trev]

Maybe I should buy some really accurate scales and weight 5 CM because that's all the spare I have.

If you buy digital scales don't keep them in your van, if you're stopped by the constabulary they may think you're using them to weigh things you shouldn't be weighing

 

[markthorpe999]

As pc says stranded cable looks bigger, it's a matter of gaining confidence in what you are looking at. It comes relatively quickly.

 

[Inteificio]

Seems I come across one problem not mentioned above.

I get supplied a lot of USA sized cables. So 2.5mm and USA measurments on the side.
My assumption is that the cable has to be bigger than both (as they rarely convert exact).

Total pain in the arse to measure by eye, trying to sight between a 4mm cable that is actually 5.4 and 6 is above me.

I just read off the side.

In the event where I can't find the size, I would find the CSA of one strand and multiply up (unsurprisingly not useful when they are fine strands).

 

[jumpin jax]

Another way to guage the size of cable is a V slot cut into a piece of aluminium or steel marked with known cable sizes alongside the V, then slide cable between slot and where it touches is the size. One can be made for cable with insulation on and one for insulation off. I hope i explained this well enough:dizzy2:

 

[wade88]

Most cables CSA is identified on the insulation where the BASEC approval print is. SWA and T&E certainly is, and flex is fairly straight forward to work out as the overall diameter of the cable does change significantly in relation to its copper CSA (unless its arctic grade i find sometimes that can require a little more attention). Be careful with SWA however as the difference in overall diameter between smaller a 4mm core and a 6mm cable for example is negligible so pay close attention to the cable print. on SWA you will typically see an identifying stamp that looks like 4 x 6 - which means 4 core 6mm cable for example. Just follow the print along until you see these figures. Im sure your well aware of this and im telling you how to suck eggs but just in case.