Twin & Earth....

[kevyn]

Hi all

Recently myself and my colleague have noticed there are two different types of PVC insulation on 6242Y cable.

We had two 100m drums of 1.5mm. One was a smaller compact drum, the other the flatter wider drum. The insulation on the smaller drum was more flexible and rubbery than the other which was harder.

Both drums came from prysmian. I am just wondering if anyone knows why they are different?

 

[Thefailsafe2012]

One roll was LSF?

 

[telectrix]

i've has some prysmian which was stiff as hell when cold.

 

[chopper76]

Twin & Earth....

Thought lsf was a different colour so it could be identified?

 

[Thefailsafe2012]

Yeah it's usually white isn't it? Didn't know if you could get it in grey though

 

[telectrix]

it's usually white.

 

[monkeyelectric]

I had a roll from the wholesalers on the last rewire i done and it was like trying to bend 25mm swa, horrible stuff!

 

[Andy78]

Maybe they changed their recipe and you got two batches ? I hope they did, prysmian is not a nice sheathing to work with.

Edit: sorry just realised you wrote insulation.

 

[chopper76]

Twin & Earth....

You prefer your ribbed I spect Andy?

 

[Andy78]

Ribbed and knobbly if possible.

 

[GLENNSPARK]

right then:
just to put things straight here about LSF...
on the old colours LSF was white....on the new colours LSF can be either white or grey....

 

[kevyn]

Twin & Earth....

I've had these two types for about 10 years so its not something new its just something I've thought about recently.

I did think it was maybe something to do with ambient temperature rating?

 

[GLENNSPARK]

Re: Twin & Earth....

I've had these two types for about 10 years so its not something new its just something I've thought about recently.

I did think it was maybe something to do with ambient temperature rating?

youv got to main grades of flat cable:
70* thermoplastic: this would be used generally in domestic rewires

90* thermosetting: this would be used for hallways & communal areas in flats etc

 

[Mr Mark Sparks]

Does lsf twin carry more than normal twin I'm sure it must but there isn't a seperate table is there..

 

[ipf]

Does lsf twin carry more than normal twin I'm sure it must but there isn't a seperate table is there..

Nah, it's almost exactly the same weight.....

 

[spark 68]

Does lsf twin carry more than normal twin I'm sure it must but there isn't a seperate table is there..

Even if it is rated to a higher temperature the accessories are only rated at 70* so the calcs stay the same.

 

[GLENNSPARK]

page 342 onwards (BGB) gives CCC for single and multicore cables at 90* thermosetting ....

 

[telectrix]

i don't think the CCCis any greater than normal T/E. LSF is just low smoke & fume, afaik

 

[GLENNSPARK]

but i know it was just in a white on the old colours...not the case now on harmonised....
it made identification easier

 

[Andy78]

LSF is marked with a B though isnt it ? Not a Y ? I might be wrong.