Thinner Low Amp Ehu Cable?

I think what's missing here is any discussion of cable type rather than conductor size. EHU cables have a considerably more robust sheath than simple 13A (or 15A) flex. The sheath is designed to be laid outdoors and regularly trampled underfoot (or run over by a vehicle) whilst remaining safe. It's possible that cable with this sheath type is only available with 2.5 sq mm conductors.
 
tonyidle said:
I think what's missing here is any discussion of cable type rather than conductor size. EHU cables have a considerably more robust sheath than simple 13A (or 15A) flex. The sheath is designed to be laid outdoors and regularly trampled underfoot (or run over by a vehicle) whilst remaining safe. It's possible that cable with this sheath type is only available with 2.5 sq mm conductors.
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Sorry to disappoint EHU cables are made from standard 3183y flex nothing special about the outer sheath apart from the recommended colour being orange.
 
lennyhb said:
Sorry to disappoint EHU cables are made from standard 3183y flex nothing special about the outer sheath apart from the recommended colour being orange.
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You're absolutely correct (just done the research I should have done before posting) :blush:

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lennyhb said:
Sorry to disappoint EHU cables are made from standard 3183y flex nothing special about the outer sheath apart from the recommended colour being orange.
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Not challenging your response but for my own interest are some not made from cable that withstand lower temperatures? Or has it still got the same "classification".
Just curious, honest!
 
Thanks Jim.(y) Thought I had seen something about it. Just when Lenny said "standard" it got me even more confuddled!:confused: Maybe it has the same class or whatever it's called.
 
JJ said:
Quote me whatever facts or figures or Ohm's law or the cooking time for lobster thermidor you want but no one will convince me that, with normal use of motorhome electrical appliances, a coiled up hook up cord will "burst into flames" or even smoulder a tiny bit.

Obviously you don't listen to me and you must follow your own inclinations!

Don't cross a road... People really do get killed doing so...

JJ :cool:
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JJ next time we meet ask Woman what happened when she used a wee Karcher pressure washer on a rolled up extension lead..

If I had not happened to smell burning plastic ( I was upstairs she was out the front but the extension was in the hallway ) we might have had no house left !

I legged it downstairs just in time to see a gout of flame ( yes, it really did go whoosh ! ) issue fifth ( it would have issued forth but I was quicker ) from the cable..
The extension lead was not too manly I admit .. it was 1.5mm stuff, but the current draw was not exactly huge either :)
It was just the fact it was coiled up and induction effects will win out every time..

Andddd.....

A couple of years ago at the Waldergrave meet in Essex in November, we had to bang on some ones door to raise the alarm !
It had not burst in to flame but was gently steaming away to its self..
When I told the guy he was nonplussed to say the least, unsure whether to believe me or not..
He put on some shoes, wandered round the back and say it for him self.. Then tried to pick it up and got a lovely wee burn for his troubles :)

( and before any one asks.. I did not unhook it in the forst instance cos for all I knew it might have been on some weird medical machine or some such !! )
 
Forgot.. I tried various roll type things and was never really happy with them..
I went back to using BIG loops and then hang from two hooks close to the floor so it is supported too.. OK, so I am a bit paranoid about cables but hey..

When it is clear up time I must look like I am doing the dance of the fairy elephant ! As I loop it I turn around so as not to put any twists in the cable

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For the attention of Mr Jaws...

Thank you for answering my post on this thread with your experience of the induction effect of a coiled cable.

With respect, I draw attention to the carefully chosen words I used in that post...

JJ said:
no one will convince me that, with normal use of motorhome electrical appliances, a coiled up hook up cord will "burst into flames" or even smoulder a tiny bit.
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As I suspected... no one has convinced me!


JJ :cool:
 
Jaws said:
It was just the fact it was coiled up and induction effects will win out every time..
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This was discussed sometime ago on facts and that Germany physicist guy (Can't remember his name) Said their is no induction effect, its all thermal. Anybody on here care to comment?

Ian

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Well I will comment thats for sure..

With DC the statement is true of course.. The amount of heat generated will depend on current drawn .. Using something as simple as Ohms law ( or even simpler Kirchoffs Law ) the heat will be evenly distributed along the entire length of the cable. And if in a coil will be held in place ( so to speak ) with no chance to sync the heat away
If you want to know more about this look up Stefan Boltzmann Law ( name pulled from a long ago distant memory so might not be spelt correctly ) concerning heat transfer

But with AC the coils radiate into each other.. and as they will be randomly phased the phases will not match which is what causes the issue.. Any current drawn will effectively be amplified by the out of phase peaks and troughs as they 'fight' one and other
That is what I was taught and subsequently used in lectures I have given.. and have proven it with coils and oscilloscope connected at three points

BUT !!!!
Like everything in life the above is little more than the opinions and findings of various folk..
And we all know about opinions don't we LOL !!!
 
Shovelheadrob said:
I do a lot of site work & it surprises me that the commonest culprits for using extension leads still wound up tight on drums are electricians, you really would think that they would know better. I haven't seen one actually burst into flames, but I have seen one that had melted to the point that it wouldn't unwind!
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So have I!
 
Jaws said:
Well I will comment thats for sure..

With DC the statement is true of course.. The amount of heat generated will depend on current drawn .. Using something as simple as Ohms law ( or even simpler Kirchoffs Law ) the heat will be evenly distributed along the entire length of the cable. And if in a coil will be held in place ( so to speak ) with no chance to sync the heat away
If you want to know more about this look up Stefan Boltzmann Law ( name pulled from a long ago distant memory so might not be spelt correctly ) concerning heat transfer

But with AC the coils radiate into each other.. and as they will be randomly phased the phases will not match which is what causes the issue.. Any current drawn will effectively be amplified by the out of phase peaks and troughs as they 'fight' one and other
That is what I was taught and subsequently used in lectures I have given.. and have proven it with coils and oscilloscope connected at three points

BUT !!!!
Like everything in life the above is little more than the opinions and findings of various folk..
And we all know about opinions don't we LOL !!!
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You also forgot to mention the other law, Sods Law. First time I don't uncoil the cable Sods Law says mine will go up in flames!
 
ScotJimland said:
and we haven't had a demo of Godwins law yet...but give it time.. give it time :LOL:
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The following statements immediately come to mind -
You're a cynical sod!:p
and
You're almost certainly correct!;)

Oh, maybe I've misunderstood. Is God Wins Law the one that says if I leave my EHU cable coiled up it and the van will go on fire and if I'm in it God wins?:getmecoat:

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I think even Funsters would be hard pressed to associate this sort of thing with the political agenda of Germany 80 years ago !! LOL !!!
 
sedge said:
Wind the cable up like washing line round your elbow,
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Please don't ever do this to my cable if you're helping me pack up! If you want to see how to coil a cable, have a look at this. . I do a lot of work theatre work with both heavy duty power and microphone cables and the only way to ensure that you can quickly and easily run out a cable or coil it up then is as the video shows. Winding a cable round your elbow is an excellent way of ruining a good cable, kinking it and making it difficult to lay out tidily.
 
Daifuse said:
Please don't ever do this to my cable if you're helping me pack up! If you want to see how to coil a cable, have a look at this. . I do a lot of work theatre work with both heavy duty power and microphone cables and the only way to ensure that you can quickly and easily run out a cable or coil it up then is as the video shows. Winding a cable round your elbow is an excellent way of ruining a good cable, kinking it and making it difficult to lay out tidily.
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Excellent video, see so many idiots wrapping the cable around their arms, I used to do sound engineering for bands.
 
Jaws said:
Well I will comment thats for sure..

With DC the statement is true of course.. The amount of heat generated will depend on current drawn .. Using something as simple as Ohms law ( or even simpler Kirchoffs Law ) the heat will be evenly distributed along the entire length of the cable. And if in a coil will be held in place ( so to speak ) with no chance to sync the heat away
If you want to know more about this look up Stefan Boltzmann Law ( name pulled from a long ago distant memory so might not be spelt correctly ) concerning heat transfer

But with AC the coils radiate into each other.. and as they will be randomly phased the phases will not match which is what causes the issue.. Any current drawn will effectively be amplified by the out of phase peaks and troughs as they 'fight' one and other
That is what I was taught and subsequently used in lectures I have given.. and have proven it with coils and oscilloscope connected at three points

BUT !!!!
Like everything in life the above is little more than the opinions and findings of various folk..
And we all know about opinions don't we LOL !!!
Click to expand...

I think he said that as both conductors where wound up together, that's the reason their was no induction effect. Sounded reasonable to me, as with trannies you only wind a single conductor. But I will take your word for it.:D

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If a tranny has only has a single winding what is the output ? I am now sort of baffled !!
 
I didn't mean a single winding, each winding will only have one conductor. With an Ehu cable both conductors are wound together, and I think that's why (Gerhard?) said you wouldn't get an induction effect. Theirs no iron core either. Sorry jaws not trying to argue with you, this outside my knowledge, just repeating what was said on facts about 3-4 years ago.

Ian
 
No argument .. interesting discussion !

The lack of an iron core will only diminish an effect.. The iron core is used to retain full effect.

Bit busy tomorrow but will run an experiment asap with a twin core lead and a low voltage AC feed.. I will set the current draw at say, 15 amps and use 15 turns of cable.. Hook up the scope and see what it looks like and what is happening..

All theory is great and leads to some really interesting postulations but try something in the physical plain and it is a good indicator :-)

I will let you know the results (y)
 
In a past life and for a very short time I helped take down telephone line wires. This stuff was cadmium copper 40lb/mile and some of it was around 100 years old. It still remembered the coils it came from & fell easily back into them.
 
When I was a young lad & we needed a magnetic screwdriver we used get a reel of thin cable (14/0.06 That takes you back) connect it to a variac and wind up the volts until well had a good field then you could magnetise or magnetise your screwdrivers etc.:)

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