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p
 
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Default joining cores of multicore cable for beter ampacity

I want to use multicore cabel for domestic instalation ,but i dont
have 2,5 mm cable.
But I have only 4 core by 1.5 mm. Can I join the cores 2 by 2 to reach
a beter ampacity?
And what MCB for this combination? The cable marker is - H05 V V - F

  #2   Report Post  
Andrew Gabriel
 
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Default joining cores of multicore cable for beter ampacity

In article .com,
"p" writes:
I want to use multicore cabel for domestic instalation ,but i dont
have 2,5 mm cable.
But I have only 4 core by 1.5 mm. Can I join the cores 2 by 2 to reach
a beter ampacity?


Not viable.

This would invoke the "conductors in parallel" part of
the regs, and it just isn't viable in the scenario you
describe as an alternative to buying the correct 2.5mm
cable in the first place.

--
Andrew Gabriel
  #3   Report Post  
p
 
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Default joining cores of multicore cable for beter ampacity

But 1.5 mm by two is a 3mm. Isn"t this combination supposed to carry a
better load than a 2.5mm.

Thank you!

  #4   Report Post  
Andy Cap
 
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Default joining cores of multicore cable for beter ampacity

On 16 Nov 2005 00:05:36 -0800, "p" wrote:

But 1.5 mm by two is a 3mm. Isn"t this combination supposed to carry a
better load than a 2.5mm.

Thank you!


Yes, but if you're determined to breach the wiring regulations why
bother asking in the first place ?

Andy
  #5   Report Post  
p
 
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Default joining cores of multicore cable for beter ampacity

I'm asking because I dont have experience in that kind of work. I juist
want to know if it is possible to use it and how much load it is
carryng. And whot ampacity of MCB to use for this.
I juist want to ack someone with better experience than me.

"" I want to use multicore cabel for domestic instalation ,but i dont
have 2,5 mm cable.
But I have only 4 core by 1.5 mm. Can I join the cores 2 by 2 to reach
a beter ampacity?
And what MCB for this combination? The cable marker is - H05 V V - F ""

Thank you!



  #6   Report Post  
gentlegreen
 
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Default joining cores of multicore cable for beter ampacity


"p" wrote in message
oups.com...
I want to use multicore cabel for domestic instalation ,but i dont
have 2,5 mm cable.
But I have only 4 core by 1.5 mm. Can I join the cores 2 by 2 to reach
a beter ampacity?
And what MCB for this combination? The cable marker is - H05 V V - F


This reminds me of my impoverished days 20 years ago when I'd just bought my
house and the interest rate was about 15 percent.

I had been given a second hand shower - so I bought some bright orange 3
core 13 amp FLEX from J Bull Electrical - I was going to double it up ;-)

A bit later I found some 10mm in a skip and hoarded that for "several"
years.

Fortunately I never actually got round to using either ......


  #7   Report Post  
p
 
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Default joining cores of multicore cable for beter ampacity

I'm asking because I dont have experience in that kind of work. I juist

want to know if it is possible to use it and how much load it is
carryng. And whot ampacity of MCB to use for this.
I juist want to ack someone with better experience than me.


"" I want to use multicore cabel for domestic instalation ,but i dont
have 2,5 mm cable.
But I have only 4 core by 1.5 mm. Can I join the cores 2 by 2 to reach
a beter ampacity?
And what MCB for this combination? The cable marker is - H05 V V - F ""



Thank you!

  #8   Report Post  
Set Square
 
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Default joining cores of multicore cable for beter ampacity

In an earlier contribution to this discussion,
Andrew Gabriel wrote:

In article .com,
"p" writes:
I want to use multicore cabel for domestic instalation ,but i dont
have 2,5 mm cable.
But I have only 4 core by 1.5 mm. Can I join the cores 2 by 2 to
reach a beter ampacity?


Not viable.

This would invoke the "conductors in parallel" part of
the regs, and it just isn't viable in the scenario you
describe as an alternative to buying the correct 2.5mm
cable in the first place.


As a matter of interest, what's the rationale for banning this? It
presumably would *work* - is it just that it may cause confusion to anyone
working on it in future?
--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is invalid.


  #9   Report Post  
 
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Default joining cores of multicore cable for beter ampacity

I imagine one issue is current sharing between the conductors. Whilst
the current share may be close to 50/50 when installed, any slightly
loose connection or corrosion of one conductor could cause one
conductor to end up carrying most of the current. not good.

  #10   Report Post  
sPoNiX
 
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Default joining cores of multicore cable for beter ampacity

On 15 Nov 2005 23:37:37 -0800, "p" wrote:

I want to use multicore cabel for domestic instalation ,but i dont
have 2,5 mm cable.
But I have only 4 core by 1.5 mm. Can I join the cores 2 by 2 to reach
a beter ampacity?
And what MCB for this combination? The cable marker is - H05 V V - F


In theory yes, but it is probably against regulations.

sponix


  #11   Report Post  
p
 
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Default joining cores of multicore cable for beter ampacity

Thanks! But anyone can tell me what kind of MCB I must use for this
cable? May be 32 Amps or lower rate?

""" I want to use multicore cabel for domestic instalation ,but i dont

have 2,5 mm cable.
But I have only 4 core by 1.5 mm. Can I join the cores 2 by 2 to reach
a beter ampacity?
And what MCB for this combination? The cable marker is - H05 V V - F """

  #13   Report Post  
Martin Bonner
 
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Default joining cores of multicore cable for beter ampacity


p wrote:
But 1.5 mm by two is a 3mm.

No. The measurement is the diameter of the core, but the current
carrying capacity is related to the cross-sectional area.

Two by 1.5mm has an area of 3.53 mm2

One by 2.5 has an area of 4.91 mm2.

Isn't this combination supposed to carry a
better load than a 2.5mm.


No. You would need three 1.5mm cores to carry more than a 2.5mm core -
and that assumes you can get all three cores to carry their fair share
of current. That is a pretty poor assumption in the long run (which is
almost certainly why parallel conductors are essentially banned in the
regs).

  #15   Report Post  
 
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Default joining cores of multicore cable for beter ampacity

If doubling a cable diameter in this fashion is not Kosha then how come
a Ring Main is legal ?

chris.



  #17   Report Post  
David Hansen
 
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Default joining cores of multicore cable for beter ampacity

On 16 Nov 2005 02:14:49 -0800 someone who may be "p"
wrote this:-

I'm asking because I dont have experience in that kind of work.


At least you are honest about that.

I juist want to know if it is possible to use it


It is possible to do most things, but not always advisable. Others
have given reasons from the wiring regulations why your course of
action is not advisable. I will give you another reason, you could
set the building on fire.

and how much load it is carryng.


How much load a cable carries depends on the load attached to it. So
far you have not said what the load is, or the type of circuit you
are interested in.

And whot ampacity of MCB to use for this.


The rating of an MCB depends on the load and type of cable it is
protecting (plus a few other things).

I juist want to ack someone with better experience than me.


Here is some advice. Don't try doing things with electricity, unless
you thoroughly know what you are doing. You may well kill yourself,
or someone else.


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54
  #18   Report Post  
Andy Dingley
 
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Default joining cores of multicore cable for beter ampacity

On 16 Nov 2005 03:10:30 -0800, "p" wrote:

Thanks! But anyone can tell me what kind of MCB I must use for this
cable? May be 32 Amps or lower rate?


The way you keep on posting, we've switched from "could tell you" to
"won't tell you".

You are doing something that is forbidden, that is forbidden for good
reason, and that is only "useful" as a sheer cheapskate measure. A major
cause of electrical problems is people trying to save a little money
like this. This is not a good thing and I doubt if anyone wants to
encourage you in doing it.

You're clearly going to do this anyway, but don't ask us to assist you.
  #19   Report Post  
 
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Default joining cores of multicore cable for beter ampacity


wrote:
If doubling a cable diameter in this fashion is not Kosha then how come
a Ring Main is legal ?


30A/32A ring circuit in 2.5mm^2 cable (or 1.5mm^2 MICC) is explicitly
excluded from Conductors in Parallel regs.

--
Andrew Gabriel

  #20   Report Post  
 
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Default joining cores of multicore cable for beter ampacity


wrote:
I imagine one issue is current sharing between the conductors. Whilst
the current share may be close to 50/50 when installed, any slightly
loose connection or corrosion of one conductor could cause one
conductor to end up carrying most of the current. not good.


Yes, that's one issue. I don't have the regs on me, but IIRC,
the conductors are required to be the same length, and without
any branches. You must show by calculation that the overload
and fault current protection will operate correctly for each conductor.
For the fault current protection, you have to consider additional
types of fault, such as one conductor shorting to ground, passing
current directly from the supply, plus that backfed from the other
end via the other conductors. Also the case where one conductor
breaks and only the backfed path is grounded, so you have a
higher earth fault loop impedance than you might otherwise
expect. For overload protection, you have to consider what
happens if one conductor breaks (without shorting). There are
probably more issues I don't recall too.

You would probably end up having to use separate but ganged
breakers for each conductor (and in the case of more than two
conductors in parallel, possibly ganged breakers at both ends of
the cable). There is simply no excuse for doing any of this in
domestic installation -- it is far cheaper to buy the correct
cable in the first place. Also, H05VV-F is flex anyway, IIRC.

--
Andrew Gabriel



  #22   Report Post  
Dave Plowman (News)
 
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Default joining cores of multicore cable for beter ampacity

In article .com,
p wrote:
I want to use multicore cabel for domestic instalation ,but i dont
have 2,5 mm cable.
But I have only 4 core by 1.5 mm. Can I join the cores 2 by 2 to reach
a beter ampacity?
And what MCB for this combination? The cable marker is - H05 V V - F


What country is this in?

--
*I took an IQ test and the results were negative.

Dave Plowman London SW
To e-mail, change noise into sound.
  #23   Report Post  
Member
 
Posts: 69
Thumbs down

Quote:
Originally Posted by p
I'm asking because I dont have experience in that kind of work. I juist

want to know if it is possible to use it and how much load it is
carryng. And whot ampacity of MCB to use for this.
I juist want to ack someone with better experience than me.


"" I want to use multicore cabel for domestic instalation ,but i dont
have 2,5 mm cable.
But I have only 4 core by 1.5 mm. Can I join the cores 2 by 2 to reach
a beter ampacity?
And what MCB for this combination? The cable marker is - H05 V V - F ""




Thank you!
Yes, go ahead!!
You have had good advice here but we can't stop you so it's your funeral.
By the way a 100 metre reel of 2.5 mm T&E is about £15.00 so can't believe cost is an issue??
  #24   Report Post  
Posted to uk.d-i-y
dennis@home
 
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Default joining cores of multicore cable for beter ampacity


wrote in message
oups.com...
I imagine one issue is current sharing between the conductors. Whilst
the current share may be close to 50/50 when installed, any slightly
loose connection or corrosion of one conductor could cause one
conductor to end up carrying most of the current. not good.


Just like a ring main then.


  #26   Report Post  
Posted to uk.d-i-y
John Rumm
 
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Default joining cores of multicore cable for beter ampacity

p wrote:

Thanks! But anyone can tell me what kind of MCB I must use for this
cable? May be 32 Amps or lower rate?


If you must do this against all sensible advice, then an MCB rating of
16A absolute maximum.



--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/
  #27   Report Post  
Posted to uk.d-i-y
gentlegreen
 
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Default joining cores of multicore cable for beter ampacity


"Peter Taylor" wrote in message
...


Just pointing out that instead of typing 1.5mm^2 or 1.5(sq)mm you can type
² by holding down the Alt key while typing 253 on the number pad on the
right of the keyboard like this: 1.5mm². 252 is cubed ³, 248 is degrees °
and 171 is ½. There's lots more.


ooh I don't know ... I don't reckon you'd get away with that in some
places - uk.misc for instance - strictly 7 bit, no smilies etc !

Thanks for the reminder - persuaded me to add "fr.rec.bricolage" to my
subscribed groups :-)
(é è ? ? )


  #28   Report Post  
Posted to uk.d-i-y
Peter Taylor
 
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Default joining cores of multicore cable for beter ampacity


"gentlegreen" wrote in
message k...

"Peter Taylor" wrote in message
...


Just pointing out that instead of typing 1.5mm^2 or 1.5(sq)mm you can
type ² by holding down the Alt key while typing 253 on the number pad on
the right of the keyboard like this: 1.5mm². 252 is cubed ³, 248 is
degrees ° and 171 is ½. There's lots more.


ooh I don't know ... I don't reckon you'd get away with that in some
places - uk.misc for instance - strictly 7 bit, no smilies etc !

Thanks for the reminder - persuaded me to add "fr.rec.bricolage" to my
subscribed groups :-)
(é è ? ? )


Mon plaisir, mon petit chou-chou! Not everybody knows about it though, do
they? We all had to learn it at some stage.

  #29   Report Post  
Posted to uk.d-i-y
Peter Taylor
 
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Default joining cores of multicore cable for beter ampacity


"John Rumm" wrote in message
...
p wrote:

Thanks! But anyone can tell me what kind of MCB I must use for this
cable? May be 32 Amps or lower rate?


If you must do this against all sensible advice, then an MCB rating of 16A
absolute maximum.


Not that this is wrong, but some of the messages on this thread are inviting
this guy to frizzle himself. For all we know, he might be trying to get
power to his 45A kiln in his shed 250 feet from the CU at the bottom of his
garden. And I don't think he understands irony/sarcasm. The advice just has
to be

DON'T DO IT

  #30   Report Post  
Posted to uk.d-i-y
Martin Bonner
 
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Default joining cores of multicore cable for beter ampacity


wrote:
If doubling a cable diameter in this fashion is not Kosha then how come
a Ring Main is legal ?

chris.


Well, mainly because I was wrong :-)



  #33   Report Post  
Posted to uk.d-i-y
Andy Dingley
 
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Default joining cores of multicore cable for beter ampacity

On Thu, 17 Nov 2005 17:15:32 -0000, "Peter Taylor"
wrote:

Not that I fully understand this, but I think these Alt-xxx characters are
indeed part of the basic ASCII set.


There are no "Alt -XX" characters, they're just characters. I use
Alt-092 regularly for "\", just because this oddball Eunuchs keyboard
doesn't have a key that every Windows box needs.

For characters up to "¦" (Alt-127) then they're 7-bit ASCII characters
and you'll find them on most keyboards. Other characters «© ½° é» etc.
are 8-bit and are found in ANSI but not ASCII character sets. They'll
work in almost all Usenet contexts (I don't think this is a
_requirement_ for usenet, but in practice it's widely supported).

Other character sets (UTF-8, ISO-8859-1 etc) that are different from
ANSI will probably not work on usenet (there will be odd "broken"
characters). They should work on the web if the server headers are
configured correctly. Some (UTF-16) won't work for usenet at all.
  #34   Report Post  
Posted to uk.d-i-y
Bob Eager
 
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Default joining cores of multicore cable for beter ampacity

On Thu, 17 Nov 2005 17:15:32 UTC, "Peter Taylor" wrote:

"Rob Morley" wrote in message
t...
In article ,
ess says...
snip
Just pointing out that instead of typing 1.5mm^2 or 1.5(sq)mm you can type
ý
by holding down the Alt key while typing 253 on the number pad on the
right
of the keyboard like this: 1.5mmý. 252 is cubed ³, 248 is degrees ø and
171
is ?. There's lots more.

|Usenet was originally a 7-bit medium, and 8-bit characters won't display
|in software that expects text to be basic ASCII. There isn't a single
|standard for an extension to the basic ASCII set anyway, so even if
|software is 8-bit capable it won't necessarily display the character
|that the author intended.

Not that I fully understand this, but I think these Alt-xxx characters are
indeed part of the basic ASCII set. It's just that there aren't enough keys
on an English QWERTY keyboard to allot one key to every available character.
Is that not right?


No. Basic ASCII uses codes between 0 and 127 decimal. And the codes
between 0 and 31 are not 'visible'. IBM's extended ASCII puts printable
characters in the 0-31 and 128-255 spaces. Any Alt-n code, where n is
not between 32 and 127 (or 126, perhaps) is not part of basic ASCII.

--
The information contained in this post is copyright the
poster, and specifically may not be published in, or used by
Avenue Supplies,
http://avenuesupplies.co.uk
  #35   Report Post  
Posted to uk.d-i-y
Mike Barnes
 
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Default joining cores of multicore cable for beter ampacity

In uk.d-i-y, Peter Taylor wrote:
"Rob Morley" wrote in message news:MPG.1de615c336
...
In article ,
says...
snip
Just pointing out that instead of typing 1.5mm^2 or 1.5(sq)mm you can
type ²
by holding down the Alt key while typing 253 on the number pad on the
right
of the keyboard like this: 1.5mm². 252 is cubed ³, 248 is degrees °
and 171
is ?. There's lots more.


|Usenet was originally a 7-bit medium, and 8-bit characters won't display
|in software that expects text to be basic ASCII. There isn't a single
|standard for an extension to the basic ASCII set anyway, so even if
|software is 8-bit capable it won't necessarily display the character
|that the author intended.

Not that I fully understand this, but I think these Alt-xxx characters
are indeed part of the basic ASCII set. It's just that there aren't
enough keys on an English QWERTY keyboard to allot one key to every
available character. Is that not right?


Yes, that's not right. Type ASCII into Google to find out more.

Here are the displayable characters of the basic ASCII character set:

! " # $ % & ' ( ) * + , - . /
0 1 2 3 4 5 6 7 8 9 : ; = ?
@ A B C D E F G H I J K L M N O
P Q R S T U V W X Y Z [ \ ] ^ _
` a b c d e f g h i j k l m n o
p q r s t u v w x y z { | } ~

The first character (above 0 and to the left of !) is the space
character, which might or might be described as "displayable" :-)

--
Mike Barnes


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Posted to uk.d-i-y
Peter Taylor
 
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Default joining cores of multicore cable for beter ampacity


"Bob Eager" wrote in message
...
On Thu, 17 Nov 2005 17:15:32 UTC, "Peter Taylor" wrote:

No. Basic ASCII uses codes between 0 and 127 decimal. And the codes
between 0 and 31 are not 'visible'. IBM's extended ASCII puts printable
characters in the 0-31 and 128-255 spaces. Any Alt-n code, where n is
not between 32 and 127 (or 126, perhaps) is not part of basic ASCII.


Thanks Bob & Andy. I just checked my binary basics and I was getting
muddled between Standard and Extended, wasn't I. Happens too often these
days!

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