I have to do a bit of pipework (15 mm copper) in my house which was build in
around 1980-1982. Because of the location I'd like to use Cuprofit fittings
in a couple of places. Having looked at the Cuprofit specs
(http://www.britishmetrics.com/pdf/tech.pdf) I note that they do not
maintain earth continuity. How can I tell if my pipework is supposed to be
earth bonded?

Incidentally, OE's spellchecker doesn't like 'Cuprofit' and suggests
'coprolite', i.e. fossilised ****. Is this a warning to me? ;-)

Ta muchly,

Steve S

--
Put both the cats out before replying.

SteveS wrote:

Incidentally, OE's spellchecker doesn't like 'Cuprofit' and suggests
'coprolite', i.e. fossilised ****. Is this a warning to me? ;-)

Yes, it is a warning. Abandon OE as soon as possible.

As for the Cuprofit, I've used them, and they are nice fittings. But I
have had one leak. I've never had a Speedfit or a Hep fitting leak. I
never worked out why it leaked. The O ring looked fine, the pipe was in
far enough.

I'm not saying don't use them - I'll be using them again. Just make sure
you pressure test everything before making the pipework inaccessible.


--
Grunff

Having looked at the Cuprofit specs
(http://www.britishmetrics.com/pdf/tech.pdf)
I note that they do not maintain earth continuity. How can I tell if my
pipework
is supposed to be earth bonded?

Well, you might not need to bother earth bonding. If you do, then it is
easily achieved with 2 earth clamps and a bit of suitably rated earth cable.
Personally, I'd be inclined not to, on the "isolation is safer than earthing
principle", especially if RCDs are installed.

However, I would still supplementary bond in a bathroom where required, as
the isolation provided would be insufficient to assure the local
equipotential zone.

Christian.

"Christian McArdle" wrote in message
et...


However, I would still supplementary bond in a bathroom where required, as
the isolation provided would be insufficient to assure the local
equipotential zone.


Thanks for the advice.

Yes, the bathroom is involved, so I'll bond. I presume I'll need 10mm earth
wire?

Cheers,

Steve S

Yes, the bathroom is involved, so I'll bond. I presume I'll need 10mm
earth
wire?

For supplementary bonding, I'd only bridge the Cuprofit if it is installed
inside the bathroom. Otherwise, just supplementary bond the section within
the bathroom to all other fittings that require it, but leave the external
Cuprofit unbridged. Ideally (which is not possible if there are electrical
fittings or other continuous earthed services) the supplementary bonded
metalwork in the bathroom will be connected to each other, but not earth.
This makes everything in the bathroom at the same voltage, but without
providing a low impedence path to earth. Of course, it is rarely possible to
achieve without plastic plumbing.

Christian.

On Fri, 23 Jul 2004 16:08:12 +0100, "Christian McArdle"
wrote:

Yes, the bathroom is involved, so I'll bond. I presume I'll need 10mm
earth
wire?

For supplementary bonding, I'd only bridge the Cuprofit if it is installed
inside the bathroom. Otherwise, just supplementary bond the section within
the bathroom to all other fittings that require it, but leave the external
Cuprofit unbridged. Ideally (which is not possible if there are electrical
fittings or other continuous earthed services) the supplementary bonded
metalwork in the bathroom will be connected to each other, but not earth.
This makes everything in the bathroom at the same voltage, but without
providing a low impedence path to earth. Of course, it is rarely possible to
achieve without plastic plumbing.

Christian.

Errrr... I must be missing something here. What is the point of connecting all
the bits of metal together but not to earth? This doesn't "make everything in
the bathroom at the same voltage". It just makes them all 'floating', just the
same as if you leave them individually 'floating'.

Tom B wrote:
On Fri, 23 Jul 2004 16:08:12 +0100, "Christian McArdle"
wrote:

Yes, the bathroom is involved, so I'll bond. I presume I'll need 10mm
earth
wire?

For supplementary bonding, I'd only bridge the Cuprofit if it is installed
inside the bathroom. Otherwise, just supplementary bond the section within
the bathroom to all other fittings that require it, but leave the external
Cuprofit unbridged. Ideally (which is not possible if there are electrical
fittings or other continuous earthed services) the supplementary bonded
metalwork in the bathroom will be connected to each other, but not earth.
This makes everything in the bathroom at the same voltage, but without
providing a low impedence path to earth. Of course, it is rarely possible to
achieve without plastic plumbing.

Christian.

Errrr... I must be missing something here. What is the point of connecting all
the bits of metal together but not to earth? This doesn't "make everything in
the bathroom at the same voltage". It just makes them all 'floating', just the
same as if you leave them individually 'floating'.

If all the metalwork/water is at the same potential, then there is no
possibility of getting across two individual appliances, one of which
has a fault, causing it to be live.

Then again...

On Fri, 23 Jul 2004 17:56:18 +0000 (UTC), Tom B wrote:

Errrr... I must be missing something here. What is the point of
connecting all the bits of metal together but not to earth? This
doesn't "make everything in the bathroom at the same voltage".

Yes it does, how can they be at (significantly) different voltages
when connected by 10mm^2...

It just makes them all 'floating', just the same as if you leave
them individually 'floating'.

The important thing is that they all float together. If they aren't
bonded then your bath taps could be at one voltage and the radiator
another.

--
Cheers
Dave. pam is missing e-mail

On Fri, 23 Jul 2004 17:56:18 +0000 (UTC), Tom B
strung together this:

Errrr... I must be missing something here. What is the point of connecting all
the bits of metal together but not to earth? This doesn't "make everything in
the bathroom at the same voltage". It just makes them all 'floating', just the
same as if you leave them individually 'floating'.

By cross-bonding everything you are holding them all at the *same *
floating potential. If you don't cross-bond them then they are at
*different* floating potentials.
--

SJW
A.C.S. Ltd