I need to run a 10mm earth bonding cable right through the house to
connect the incoming rising main (by the back door) to the main earthing
point next to the CU (by the front door - great!).

Do I need to do this using one unbroken length of cable, or am I allowed
to make a crimped joint to connect two shorter lengths? Reason is that
of course I have a long piece on my reel, but it's just too short to
reach right through the house and I'd rather use it unless the regs say
I can't.

Thanks
David

On Mon, 27 Jun 2005 19:59:42 GMT,it is alleged that Lobster
spake thusly in uk.d-i-y:

I need to run a 10mm earth bonding cable right through the house to
connect the incoming rising main (by the back door) to the main earthing
point next to the CU (by the front door - great!).

Do I need to do this using one unbroken length of cable, or am I allowed
to make a crimped joint to connect two shorter lengths? Reason is that
of course I have a long piece on my reel, but it's just too short to
reach right through the house and I'd rather use it unless the regs say
I can't.

Thanks
David

I have no clue whether the regs permit this or not. I would however
not suggest crimps in this case, personal preference would be a proper
earth block at some accessible and not damp location, such as a
cupboard, in a box with a blank plate on the front, labelled with the
'safety electrical connection - do not remove' sign.

As these earth blocks are often designed for 4-8 conductors, I would
run the earth wire through, double it back and run it into the next
connector, kind of forming two upside down U shapes, such that each
part is clamped by 4 screws. Probably overkill, but the blocks are
cheaper than a huge length of 10mm :-)

However, I would seriously advise waiting for other responses from
this group as many are knowledgable about the regulations in detail
and may know if this is forbidden.

HTH

--
Life is like a hot bath. It feels good while you're in it, but the
longer you stay in, the more wrinkled you get.
- Robbert Oustin

"Lobster" wrote in message
...
I need to run a 10mm earth bonding cable right through the house to
connect the incoming rising main (by the back door) to the main earthing
point next to the CU (by the front door - great!).

Do I need to do this using one unbroken length of cable, or am I allowed
to make a crimped joint to connect two shorter lengths? Reason is that
of course I have a long piece on my reel, but it's just too short to
reach right through the house and I'd rather use it unless the regs say
I can't.

Thanks
David

As in all bonding practices, this one must be done un-broken. Joints only
create resistive points along the conductor, so are not a good idea in
safety bonding.

Lobster wrote:

I need to run a 10mm earth bonding cable [...]

Do I need to do this using one unbroken length of cable, or am I allowed
to make a crimped joint to connect two shorter lengths?

A joint is allowed. Joints in protective conductors like this are
subject to the same rules as any other joints - i.e. they must be sound
and protected from corrosion, etc. and must be accessible if not
crimped, welded, brazed, soldered or resin potted.

An in-line crimped joint will be fine in a reasonably dry location. I'd
protect it with overall heatshrink sleeving, although that's not
actually required for sizes of 10mm^2 and over. Bear in mind that
10mm^2 is beyond the range of the usual insulated crimps so you'll need
to beg, borrow or hire the appropriate heavier duty crimp tool and the
correct crimp 'lug'.

--
Andy

Andy Wade wrote:
Lobster wrote:

I need to run a 10mm earth bonding cable [...]

Do I need to do this using one unbroken length of cable, or am I
allowed to make a crimped joint to connect two shorter lengths?


A joint is allowed. Joints in protective conductors like this are
subject to the same rules as any other joints - i.e. they must be sound
and protected from corrosion, etc. and must be accessible if not
crimped, welded, brazed, soldered or resin potted.

An in-line crimped joint will be fine in a reasonably dry location. I'd
protect it with overall heatshrink sleeving, although that's not
actually required for sizes of 10mm^2 and over. Bear in mind that
10mm^2 is beyond the range of the usual insulated crimps so you'll need
to beg, borrow or hire the appropriate heavier duty crimp tool and the
correct crimp 'lug'.

Ah, the joys of uk.d-i-y! Thanks for the replies - but so far I have
one "don't know", one "no" and one "yes"! I'll wait and hope that a
consensus is reached... or can anyone give me a definitive source with
the ccorrect answer?

If it's allowed, then I must admit I'd overlooked Andy's point that my
crimping tool will be too small; so I'd probably end up usig Chip's
solution with an earth block instead.

--
David

In article ,
Lobster wrote:

If it's allowed, then I must admit I'd overlooked Andy's point
that my crimping tool will be too small; so I'd probably end up
usig Chip's solution with an earth block instead.

Years ago the approved way of jointing two thick
wires was to hold them parallel and tightly wind
onto them a 'spring' of about 26swg tinned copper
wire. Then solder together. The spring provided
the mechanical strength, and avoided the need to
twist (and possibly weaken) the thick wires.
Tidier for sleeving as well.

--
Tony Williams.

Would you not be allowed to make a second Earthing Plate near to your rising
water main. In a 1935 Household book it told you how to dig an Earth Pit. A
Zinc plate, household soot, sand and earth. All this about one foot down. I
believe these days you can just whack a Copper spike in and connect to it.


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BigWallop wrote:
"Lobster" wrote in message
...
I need to run a 10mm earth bonding cable right through the house to
connect the incoming rising main (by the back door) to the main earthing
point next to the CU (by the front door - great!).

Do I need to do this using one unbroken length of cable, or am I allowed
to make a crimped joint to connect two shorter lengths? Reason is that
of course I have a long piece on my reel, but it's just too short to
reach right through the house and I'd rather use it unless the regs say
I can't.

Thanks
David

As in all bonding practices, this one must be done un-broken. Joints only
create resistive points along the conductor, so are not a good idea in
safety bonding.

So explain why it is allowed to bond one water pipe to another where
you have a screwed clamp at each end of the wire plus the "joints" of
the things that clamp around each pipe.

You're saying every piece of pipe must be bonded individually to the
main earth by a single unbroken length of wire.

MBQ

wrote:


BigWallop wrote:
"Lobster" wrote in message
...
I need to run a 10mm earth bonding cable right through the house to
connect the incoming rising main (by the back door) to the main earthing
point next to the CU (by the front door - great!).

Do I need to do this using one unbroken length of cable, or am I allowed
to make a crimped joint to connect two shorter lengths? Reason is that
of course I have a long piece on my reel, but it's just too short to
reach right through the house and I'd rather use it unless the regs say
I can't.

Thanks
David

As in all bonding practices, this one must be done un-broken. Joints only
create resistive points along the conductor, so are not a good idea in
safety bonding.

So explain why it is allowed to bond one water pipe to another where
you have a screwed clamp at each end of the wire plus the "joints" of
the things that clamp around each pipe.

You're saying every piece of pipe must be bonded individually to the
main earth by a single unbroken length of wire.

The requirement is that 'main bonding' to the incoming water (and gas
if you have it) pipes is done with a continuous unbroken length of
wire from the main bonding connecting block adjacent to (or maybe in)
your consumer unit. Supplementary bonding (as is required in
bathrooms and similar places) doesn't have to be done with a single
piece of wire.

--
Chris Green

In article ,
writes:
BigWallop wrote:
As in all bonding practices, this one must be done un-broken. Joints only
create resistive points along the conductor, so are not a good idea in
safety bonding.

The requirement is that 'main bonding' to the incoming water (and gas
if you have it) pipes is done with a continuous unbroken length of
wire from the main bonding connecting block adjacent to (or maybe in)
your consumer unit.

This isn't true.
If you believe it to be so, please cite the regulation number.

--
Andrew Gabriel

Lobster wrote:
Andy Wade wrote:

Lobster wrote:

I need to run a 10mm earth bonding cable [...]

Do I need to do this using one unbroken length of cable, or am I
allowed to make a crimped joint to connect two shorter lengths?

A joint is allowed. Joints in protective conductors like this are
subject to the same rules as any other joints - i.e. they must be
sound and protected from corrosion, etc. and must be accessible if not
crimped, welded, brazed, soldered or resin potted.

An in-line crimped joint will be fine in a reasonably dry location.
I'd protect it with overall heatshrink sleeving, although that's not
actually required for sizes of 10mm^2 and over. Bear in mind that
10mm^2 is beyond the range of the usual insulated crimps so you'll
need to beg, borrow or hire the appropriate heavier duty crimp tool
and the correct crimp 'lug'.

Ah, the joys of uk.d-i-y! Thanks for the replies - but so far I have
one "don't know", one "no" and one "yes"! I'll wait and hope that a
consensus is reached... or can anyone give me a definitive source with
the ccorrect answer?

I now make the score three-two in favour of the 'Yes' camp...
Where do I go for a definitive answer? My newly-expert BCO? ;-)

--
David

These days the bonding of water pipes is only to prevent the build up of
static electricity as you can have plastic, non conducting, fittings in
between pipes. The Earthing is not actually used as a Safety Earth in this
case.


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On Tue, 28 Jun 2005 17:18:28 GMT, Lobster wrote:

I now make the score three-two in favour of the 'Yes' camp...
Where do I go for a definitive answer? My newly-expert BCO? ;-)

The Onsite Guide only has note in te various diagrams which says:

"Main equipotential bonding conductors maybe seperate (as shown) or
looped with unbroken conductors"

The "(as shown)" refers to seperate conductors from the main earth
terminal to metal services pipes. The "looped with unbroken
conductors" implies that broken conductors between the main earth
terminal and the metal service pipe is not allowed. Therefore it ought
to be a single length of cable.

--
Cheers
Dave. pam is missing e-mail

"Chris McBrien" wrote in message
. ..
These days the bonding of water pipes is only to prevent the build up of
static electricity as you can have plastic, non conducting, fittings in
between pipes. The Earthing is not actually used as a Safety Earth in this
case.


So protection against indirect contact isn't the reason anymore then?

S'funny I always thought the idea was to provide a low resistance path for
current to flow resulting in the fuse or circuit breaker operating and
disconnecting fault from the supply especially in cases where the house
pipework is copper and the underground supply is in non conductive plastic.
Perhaps you know differently?

On Tuesday, in article

"Lobster" wrote:

Ah, the joys of uk.d-i-y! Thanks for the replies - but so far I have
one "don't know", one "no" and one "yes"! I'll wait and hope that a
consensus is reached... or can anyone give me a definitive source with
the ccorrect answer?

"Ask not your question upon the Usenet, for answers there will come
three: 'Yea', and 'Nay', and 'Try a different newsgroup'."

;-)

--
Brian {Hamilton Kelly}
"Je n'ai fait celle-ci plus longue que parce que je n'ai pas eu
le loisir de la faire plus courte."
Blaise Pascal, /Lettres Provinciales/, 1657

In article ,
"Chris writes:
These days the bonding of water pipes is only to prevent the build up of
static electricity as you can have plastic, non conducting, fittings in
between pipes. The Earthing is not actually used as a Safety Earth in this
case.

Where on earth did you read that?

--
Andrew Gabriel

In message om,
"Dave Liquorice" wrote:

On Tue, 28 Jun 2005 17:18:28 GMT, Lobster wrote:

I now make the score three-two in favour of the 'Yes' camp...
Where do I go for a definitive answer? My newly-expert BCO? ;-)

The Onsite Guide only has note in te various diagrams which says:

"Main equipotential bonding conductors maybe seperate (as shown) or
looped with unbroken conductors"

The "(as shown)" refers to seperate conductors from the main earth
terminal to metal services pipes. The "looped with unbroken
conductors" implies that broken conductors between the main earth
terminal and the metal service pipe is not allowed. Therefore it ought
to be a single length of cable.


The problem is that neither BS7671 nor the OSG is specific on this
matter. There is no paragraph in either (AFAICS) which categorically
states "main EP bonding conductors must be unbroken between the main
earthing terminal and the connection point to the service pipe". The
phrase quoted is the closest you get to that, and IMO specifically
refers to the situation where there is one wire which runs from the main
earthing terminal first to one service and then to another. It is an
annotation to an example diagram and isn't referred to in the text of
the OSG, and doesn't refer to a paragraph number in BS7671.

It is *probably* meant to guard against the situation where the
connection to the first service becomes loose. Where two wires are run,
the second service will still be connected and since the services (e.g.
gas & water) are usually connected metalically somewhere, a measure of
bonding still applies. If there is just one cable, and it is broken
(i.e. two lengths were used) at the first service, the connection to the
second may also be lost. A single length of cable will not suffer here.

Having said that, I have always run single continuous lengths for the
main bond, and have never jointed. I would consider a joint where
replacing the whole run would be impractical, but impractical does not
include "the run is 15m and I've only 12m of cable left on the drum".

Hwyl!

M.

--
Martin Angove: http://www.tridwr.demon.co.uk/
Two free issues: http://www.livtech.co.uk/ Living With Technology
.... Wibble Wobble Fishcakes.

In message ,
"Chris wrote:

Would you not be allowed to make a second Earthing Plate near to your rising
water main. In a 1935 Household book it told you how to dig an Earth Pit. A
Zinc plate, household soot, sand and earth. All this about one foot down. I
believe these days you can just whack a Copper spike in and connect to it.


Things have moved on a long way since 1935. In particular you can't
"just whack a Copper spike in" because a wire isn't long enough. The
idea is to bond metallic services so that they are all at substantially
the same potential, and therefore they really need to be physically
connected to the same earthing point. There are situations where two or
more separate earthing systems are permitted, but I really don't see
how they could apply in a domestic situation... erm... you *are* aware
that this is *uk*.d-i-y?

Might I respectfully suggest, in the light of Part P, and particularly
regarding your "static" answer elsewhere in the thread that you refrain
from answering questions unless you have evidence (e.g. reference to
BS7671) to back up your assertion?

Hwyl!

M.

--
Martin Angove: http://www.tridwr.demon.co.uk/
Two free issues: http://www.livtech.co.uk/ Living With Technology
.... This tagline was reclaimed and is not yet stolen.

In article ,
Martin Angove wrote:
Having said that, I have always run single continuous lengths for the
main bond, and have never jointed. I would consider a joint where
replacing the whole run would be impractical, but impractical does not
include "the run is 15m and I've only 12m of cable left on the drum".

Absolutely. I've never jointed cable to get the last bit on the drum used
up - since that suggests you'll never need any more ever.

It's not exactly expensive after all.

--
*The modem is the message *

Dave Plowman London SW
To e-mail, change noise into sound.

Andrew Gabriel wrote:
In article ,
writes:
BigWallop wrote:
As in all bonding practices, this one must be done un-broken. Joints only
create resistive points along the conductor, so are not a good idea in
safety bonding.

The requirement is that 'main bonding' to the incoming water (and gas
if you have it) pipes is done with a continuous unbroken length of
wire from the main bonding connecting block adjacent to (or maybe in)
your consumer unit.

This isn't true.
If you believe it to be so, please cite the regulation number.

The OSG says "Main equipotential bonding conductors maybe seperate
(as shown) or looped with unbroken conductors", this is discussed to
death further down the thread so I won't say anything further here. :-)

--
Chris Green

On Tuesday, in article
"Tony Williams" wrote:

Years ago the approved way of jointing two thick
wires was to hold them parallel and tightly wind
onto them a 'spring' of about 26swg tinned copper
wire. Then solder together. The spring provided
the mechanical strength, and avoided the need to
twist (and possibly weaken) the thick wires.
Tidier for sleeving as well.

Errm, by 'spring' do you mean helix?

(There's nothing springlike about BTC)

--
Brian {Hamilton Kelly}
"Je n'ai fait celle-ci plus longue que parce que je n'ai pas eu
le loisir de la faire plus courte."
Blaise Pascal, /Lettres Provinciales/, 1657

Martin Angove wrote:

[OSG note (i) to Figs, 4a, 4b & 4c]

It is *probably* meant to guard against the situation where the
connection to the first service becomes loose.

I'd suggest it is meant to maintain the bonding to the other services in
the event that the clamp to an intermediate service is removed
(temporarily or permanently) in connection with work being done on that
service. E.g. if a metal service pipe is replaced in plastic the clamp
can be removed safely and continuity is maintained without the need for
any electrical knowledge by the plumber/gasfitter etc. The plumber
(etc.) would have to deliberately cut the wire to disrupt the bonding.

I don't see that this in any way forbids the use of a properly-made
in-line joint in a bonding conductor. In any case the main bonding
conductor(s) have to be disconnectable from the main earth terminal for
test purposes - so there's one joint to start with...

Having said that, I have always run single continuous lengths for the
main bond, and have never jointed. I would consider a joint where
replacing the whole run would be impractical, but impractical does not
include "the run is 15m and I've only 12m of cable left on the drum".

I agree, but there's nothing in section 543-03 of BS 7671 -
"Preservation of electrical continuity of protective conductors" that
specifically bans such joints. There are only 6 regulations in this group:

543-03-01 requires suitable protection against mechanical and chemical
deterioration, and electrodynamic effects;

543-03-02 requires separate protective conductors (PCs) up to and
including 6mm^2 to be insulated and requires sleeving of the bare PC of
a multi-core cable (e.g. T&E) at terminations;

543-03-03 requires connections to comply with the accessibility
requirements of section 526-04 (i.e. as for live conductors). Joints in
metal conduit or trunking systems used as PCs are excluded from this;

543-03-04 forbids the use of switching devices in PCs (with certain
exceptions). It also says "Joints which can be disconnected for test
purposes are permitted in a protective conductor circuit."

543-03-05 is concerned with earth monitoring systems with pilot wires
(not usually relevant to TN systems or house wiring).

543-03-06 requires joints in metal conduit to be screwed or to use
"substantial mechanical clamps" and forbids the use of "plain slip or
pin-grip sockets."

--
Andy

In message ,
Andy Wade wrote:

Martin Angove wrote:

[OSG note (i) to Figs, 4a, 4b & 4c]

It is *probably* meant to guard against the situation where the
connection to the first service becomes loose.

I'd suggest it is meant to maintain the bonding to the other services in
the event that the clamp to an intermediate service is removed
(temporarily or permanently) in connection with work being done on that
service. E.g. if a metal service pipe is replaced in plastic the clamp
can be removed safely and continuity is maintained without the need for
any electrical knowledge by the plumber/gasfitter etc. The plumber
(etc.) would have to deliberately cut the wire to disrupt the bonding.


Good point, hadn't thought of that. I'm not sure how often that is
likely to happen though; on the incoming side, perhaps, but on the
outgoing side it'd have to be a pretty major refurbishment to warrant
replacing with plastic right back to the tap. Mind you, I can't see one
of those straps coming loose without an earthquake either :-)

A point arising though is what to do with the disconnected bond? You'll
be left with a length (inch to inch and a half) of G&Y which has been
stripped of insulation and hence requires protecting from damage and the
elements and accidental shorting on something it shouldn't. Would a tape
wrap be sufficient, or would we be looking at enclosing in some kind of
a box? Would a plumber necessarily think of such things?

Had a job last week where I renewed the bond to the water pipework. The
kitchen fitters (about 2 years ago) had simply disconnected the original
bond and left it dangling behind a unit. It was green 6mm2 and I needed
(for other reasons) to upgrade to 10mm2, but why on earth (sorry) did
they just leave it dangling when presumably it was previously attached?

I don't see that this in any way forbids the use of a properly-made
in-line joint in a bonding conductor. In any case the main bonding
conductor(s) have to be disconnectable from the main earth terminal for
test purposes - so there's one joint to start with...

Having said that, I have always run single continuous lengths for the
main bond, and have never jointed. I would consider a joint where
replacing the whole run would be impractical, but impractical does not
include "the run is 15m and I've only 12m of cable left on the drum".

I agree, but there's nothing in section 543-03 of BS 7671 -
"Preservation of electrical continuity of protective conductors" that
specifically bans such joints.

No, and I think I said that, or at least implied that, in my post. I was
just trying to avoid quoting large chunks of BS7671 ;-)

Hwyl!

M.

--
Martin Angove: http://www.tridwr.demon.co.uk/
Two free issues: http://www.livtech.co.uk/ Living With Technology
.... Artificial Intelligence: The other guy's opinion.

In article ,
Brian {Hamilton Kelly} wrote:

Errm, by 'spring' do you mean helix?

A 'spring' is what it was known as.

--
Tony Williams.

DO NOT do this!! You will introduce different earth potentials on the property! The entire house has to be "one equipotential zone"