4mm & 6mm T&E cable

[AndyPRK]

I won some 4mm and 6mm cable (old colours) from different people.

However now I have them side by side they look the same thickness!

I'm not sure which is correct though. I am doubting the 6mm is correct.

Are there markings on the side to indicate 4mm etc or just BS numbers ?

I have a verna caliper, but I was measuring about 3mm on both. Is it as easy as just measuring ?

Thanks for your help.

 

[EdwardCurrent]

Hello Andy.
The size is given as the cross sectional area.

Overall
4mm can be 6.10 x 11.6 mm
6mm can be 6.9 x 13.3 mm

Yo could cut a bit off and go to b&q or the like and compare it.
Hope this helps

Ed

 

[sparkyspike]

Are you measuring the thickness of the whole cable? Insulation varies according to brand, so maybe try measuring each strand of wire with your calipers and comparing them with each other.

 

[ericmark]

4mm² = 2.55mm and 6mm² = 3.12mm see here for details on twin and earth cable I use a yellow crimp tight = 6mm² and slack = 4mm²

 

[Spark123]

Or if you want to be technical you can use your vernier to measure a single strand, work out the area of each strand by dividing by 2 to give you the radius, and solving pi r², then multiplying the result by the no of strands (usually 7)

If I have done my math right a single strand for 6mm 7 strand has a diamether of about 1.044mm and a single strand for 4mm about 0.853mm

 

[ban-all-sheds]

If you cut through the insulation on one core, slide it along a bit to expose a few mm of copper, then twist the core so that it tightens up as much as possible, and then measure the diameter of that, as your vernier caliper will read to a precision of at least 1 DP, you'll be able to tell which is which, as the difference in diameter is significant enough.

 

[AndyPRK]

some excellent replies thanks.

good idea's to goto b&q or use a yellow crimp to test size.

I had removed the insulation and was measuring the copper only, but I hadn't twisted them tight.

 

[Taylortwocities]

The best way to tell the difference is to measure the csa of the cpc.

In a 4mm t&E it will be 1.5mm²
in 6mm T&E it is 2.5mm²

both cables have solid conductors for the cpc so u can check it with red and blue crimps. If your red crimp doesnt go over the cpc then you've probably got 6mm² cable.

more info at http://www.eandeelectricalshop.co.uk/CablePDF's\6242.pdf

 

[AndyPRK]

I followed the above steps in all posts but the last.

I think the information contridicts through if you follow all advice. Maybe some of the numbers are mixed up ?

I tried the yellow crimp trick and it was a loose fit on both.

I have ordered some more 6mm and i'll see if that helps conclude for sure !

I did wonder whether anything could be concluded from the CPC, so thanks for pointing that out.

 

[AndyPRK]

checked the CPC

Measures 1.7mm (closer to 1.5mm then)

A red crimp will go on if forced

 

[RF Lighting]

Are you sure you haven't been sold 4.0mm² as 6.0mm²

 

[Spark123]

Can you use your vernier to measure a single strand of the 7 core wire?

 

[Taylortwocities]

Please remember that we are talking cross sectional area, not the diameter so you'll need to use πr²

 

[sjwkmje]

Please remember that we are talking cross sectional area, not the diameter so you'll need to use πr²

Its PI * R² where PI is 3.1415. Just makes it easier as π symbol could be confusing.

Adam

 

[AndyPRK]

Are you sure you haven't been sold 4.0mm² as 6.0mm²

That's why I started this thread. To answer that exact question.

Will find out in a few days.