I've a question about the earthing connections on our domestic plumbing.
I can see that there is a wire in parallel to our water meter, but I'm
not sure that this can be the main earth because the supply pipe is
plastic. I can also see a wire going into the wall under the sink, so
my assumption here is that it mainly uses the electrical earth. But
there are speedfit connectors under there, which I expect are not
conductive, so there are parts (e.g. pipes feeding taps) that are
isolated from the rest. I'm not worried about this (although perhaps I
should be?), since all this was supposedly done by professionals; but I
thought I'd ask here if every single section of pipe is meant to be
individually earthed, or if that would not really be practical. Does it
even make sense to earth, for example, braided tap tails?

On 05/05/2020 12:36, Dan S. MacAbre wrote:

I've a question about the earthing connections on our domestic plumbing.
Â*I can see that there is a wire in parallel to our water meter, but I'm
not sure that this can be the main earth because the supply pipe is
plastic.Â* I can also see a wire going into the wall under the sink, so
my assumption here is that it mainly uses the electrical earth.Â* But
there are speedfit connectors under there, which I expect are not
conductive, so there are parts (e.g. pipes feeding taps) that are
isolated from the rest.Â* I'm not worried about this (although perhaps I
should be?)

Generally nothing to worry about, if all we are discussing is
equipotential bonding.

, since all this was supposedly done by professionals;

Given many of them seem to flounder a little on this particular subject,
that is not always an assurance of anything!

but I
thought I'd ask here if every single section of pipe is meant to be
individually earthed,

Short answer - no.

or if that would not really be practical.Â* Does it
even make sense to earth, for example, braided tap tails?

Not really.

Firstly, this is not about earthing as such, but equipotential bonding -
different things, with different objectives that work in different ways.
However they do often use the same green/yellow insulated wire, and
there are situations where the systems interact.

In its simplest terms, earthing is designed to prevent electrical fires,
and limit the maximum duration of a an electric shock.

Equipotential bonding is designed to limit the magnitude of an electric
shock (i.e. reduce the current that can flow into the victim, by
limiting the voltage (or potential difference) across their body).

EQ bonding is used in places where you are likely to be more
unacceptable to the influence of a shock (e.g. when wet / naked). The
primary question ask when deciding what needs bonding, is "Is this
conductive part actually capable of introducing a potential into the
area". So a length of metal water pipe that comes from elsewhere in the
house to your bath tap, certainly could, and hence needs bonding. A
short section of copper "show work" pipe on the end of a feed in
plastic, does not, since it can't bring a potential in from outside the
zone.

Have a read through this for a fuller explanation:

http://wiki.diyfaq.org.uk/index.php/...ng_and_Bonding


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 05/05/2020 12:36, Dan S. MacAbre wrote:
I've a question about the earthing connections on our domestic plumbing.
Â*I can see that there is a wire in parallel to our water meter, but I'm
not sure that this can be the main earth because the supply pipe is
plastic.Â* I can also see a wire going into the wall under the sink, so
my assumption here is that it mainly uses the electrical earth.Â* But
there are speedfit connectors under there, which I expect are not
conductive, so there are parts (e.g. pipes feeding taps) that are
isolated from the rest.Â* I'm not worried about this (although perhaps I
should be?), since all this was supposedly done by professionals; but I
thought I'd ask here if every single section of pipe is meant to be
individually earthed, or if that would not really be practical.Â* Does it
even make sense to earth, for example, braided tap tails?

Your water pipes shouldn't be used to earth your wiring (though they
commonly were in the past). You should have something separate at your
consumer unit/fusebox.

What I think you are looking at is Main Bonding and Supplementary
Bonding. I think you may well be OK on both but suggest you look at

http://wiki.diyfaq.org.uk/index.php/...ng_and_Bonding

and ask again if you still have questions - when people who know better
than me can help.

As for earthing, you can see what things typically look like at

http://wiki.diyfaq.org.uk/index.php/Earthing_Types

If that leaves you with questions about just what you've got it'd help
if you could share [photos somewhere

--
Robin
reply-to address is (intended to be) valid

John Rumm wrote:
On 05/05/2020 12:36, Dan S. MacAbre wrote:

I've a question about the earthing connections on our domestic
plumbing. Â*Â*I can see that there is a wire in parallel to our water
meter, but I'm not sure that this can be the main earth because the
supply pipe is plastic.Â* I can also see a wire going into the wall
under the sink, so my assumption here is that it mainly uses the
electrical earth.Â* But there are speedfit connectors under there,
which I expect are not conductive, so there are parts (e.g. pipes
feeding taps) that are isolated from the rest.Â* I'm not worried about
this (although perhaps I should be?)

Generally nothing to worry about, if all we are discussing is
equipotential bonding.

, since all this was supposedly done by professionals;

Given many of them seem to flounder a little on this particular subject,
that is not always an assurance of anything!


Well, I can tell from some of things I've found that they weren't the
best available.

but I thought I'd ask here if every single section of pipe is meant to
be individually earthed,

Short answer - no.

or if that would not really be practical.Â* Does it even make sense to
earth, for example, braided tap tails?

Not really.

Firstly, this is not about earthing as such, but equipotential bonding -
different things, with different objectives that work in different ways.
However they do often use the same green/yellow insulated wire, and
there are situations where the systems interact.

In its simplest terms, earthing is designed to prevent electrical fires,
and limit the maximum duration of a an electric shock.

Equipotential bonding is designed to limit the magnitude of an electric
shock (i.e. reduce the current that can flow into the victim, by
limiting the voltage (or potential difference) across their body).

EQ bonding is used in places where you are likely to be more
unacceptable to the influence of a shock (e.g. when wet / naked). The
primary question ask when deciding what needs bonding, is "Is this
conductive part actually capable of introducing a potential into the
area". So a length of metal water pipe that comes from elsewhere in the
house to your bath tap, certainly could, and hence needs bonding. A
short section of copper "show work" pipe on the end of a feed in
plastic, does not, since it can't bring a potential in from outside the
zone.

Have a read through this for a fuller explanation:

http://wiki.diyfaq.org.uk/index.php/...ng_and_Bonding


Brilliant. Thanks.

Robin wrote:
On 05/05/2020 12:36, Dan S. MacAbre wrote:
I've a question about the earthing connections on our domestic
plumbing. Â*Â*I can see that there is a wire in parallel to our water
meter, but I'm not sure that this can be the main earth because the
supply pipe is plastic.Â* I can also see a wire going into the wall
under the sink, so my assumption here is that it mainly uses the
electrical earth.Â* But there are speedfit connectors under there,
which I expect are not conductive, so there are parts (e.g. pipes
feeding taps) that are isolated from the rest.Â* I'm not worried about
this (although perhaps I should be?), since all this was supposedly
done by professionals; but I thought I'd ask here if every single
section of pipe is meant to be individually earthed, or if that would
not really be practical.Â* Does it even make sense to earth, for
example, braided tap tails?

Your water pipes shouldn't be used to earth your wiring (though they
commonly were in the past).Â* You should have something separate at your
consumer unit/fusebox.


I'm assuming it is the other way around - the mains earth is being used
to earth the water pipes. The wire is coming out of original plaster
(whoever did the kitchen didn't plaster over anything that wasn't on
show), so it has been there since the mid 80's.

What I think you are looking at isÂ* Main Bonding and Supplementary
Bonding. I think you may well be OK on both but suggest you look at

http://wiki.diyfaq.org.uk/index.php/...ng_and_Bonding

and ask again if you still have questions - when people who know better
than me can help.

As for earthing, you can see what things typically look like at

http://wiki.diyfaq.org.uk/index.php/Earthing_Types

If that leaves you with questions about just what you've got it'd help
if you could share [photos somewhere


Thanks for the links. I'll read them, but I'm not going to worry about
what's going on here.

On 05/05/2020 15:19, Dan S. MacAbre wrote:
Robin wrote:
On 05/05/2020 12:36, Dan S. MacAbre wrote:
I've a question about the earthing connections on our domestic
plumbing. Â*Â*I can see that there is a wire in parallel to our water
meter, but I'm not sure that this can be the main earth because the
supply pipe is plastic.Â* I can also see a wire going into the wall
under the sink, so my assumption here is that it mainly uses the
electrical earth.Â* But there are speedfit connectors under there,
which I expect are not conductive, so there are parts (e.g. pipes
feeding taps) that are isolated from the rest.Â* I'm not worried about
this (although perhaps I should be?), since all this was supposedly
done by professionals; but I thought I'd ask here if every single
section of pipe is meant to be individually earthed, or if that would
not really be practical.Â* Does it even make sense to earth, for
example, braided tap tails?

Your water pipes shouldn't be used to earth your wiring (though they
commonly were in the past).Â* You should have something separate at
your consumer unit/fusebox.


I'm assuming it is the other way around - the mains earth is being used
to earth the water pipes.Â* The wire is coming out of original plaster
(whoever did the kitchen didn't plaster over anything that wasn't on
show), so it has been there since the mid 80's.

What I think you are looking at isÂ* Main Bonding and Supplementary
Bonding. I think you may well be OK on both but suggest you look at

http://wiki.diyfaq.org.uk/index.php/...ng_and_Bonding

and ask again if you still have questions - when people who know
better than me can help.

As for earthing, you can see what things typically look like at

http://wiki.diyfaq.org.uk/index.php/Earthing_Types

If that leaves you with questions about just what you've got it'd help
if you could share [photos somewhere


Thanks for the links.Â* I'll read them, but I'm not going to worry about
what's going on here.

I used to have a kitchen sink that would sometimes give you a tingle. It
didn't after I added bonding, but neither did that trip the RCD. I never
found out what was causing it.

newshound wrote:
On 05/05/2020 15:19, Dan S. MacAbre wrote:
Robin wrote:
On 05/05/2020 12:36, Dan S. MacAbre wrote:
I've a question about the earthing connections on our domestic
plumbing. Â*Â*I can see that there is a wire in parallel to our water
meter, but I'm not sure that this can be the main earth because the
supply pipe is plastic.Â* I can also see a wire going into the wall
under the sink, so my assumption here is that it mainly uses the
electrical earth.Â* But there are speedfit connectors under there,
which I expect are not conductive, so there are parts (e.g. pipes
feeding taps) that are isolated from the rest.Â* I'm not worried
about this (although perhaps I should be?), since all this was
supposedly done by professionals; but I thought I'd ask here if
every single section of pipe is meant to be individually earthed, or
if that would not really be practical.Â* Does it even make sense to
earth, for example, braided tap tails?

Your water pipes shouldn't be used to earth your wiring (though they
commonly were in the past).Â* You should have something separate at
your consumer unit/fusebox.


I'm assuming it is the other way around - the mains earth is being
used to earth the water pipes.Â* The wire is coming out of original
plaster (whoever did the kitchen didn't plaster over anything that
wasn't on show), so it has been there since the mid 80's.

What I think you are looking at isÂ* Main Bonding and Supplementary
Bonding. I think you may well be OK on both but suggest you look at

http://wiki.diyfaq.org.uk/index.php/...ng_and_Bonding

and ask again if you still have questions - when people who know
better than me can help.

As for earthing, you can see what things typically look like at

http://wiki.diyfaq.org.uk/index.php/Earthing_Types

If that leaves you with questions about just what you've got it'd
help if you could share [photos somewhere


Thanks for the links.Â* I'll read them, but I'm not going to worry
about what's going on here.

I used to have a kitchen sink that would sometimes give you a tingle. It
didn't after I added bonding, but neither did that trip the RCD. I never
found out what was causing it.

I had a metal light switch that did that. I found that the earthing
wire in the lighting daisy-chain (they hadn't bothered to close the loop
at one of the ends) wasn't connected in one of the roses, which meant
that the rest of them further down the chain weren't earthed. I
measured an induced voltage of 70V on the faceplate. Fixing the
non-connected earth wire solved the problem. It only gave a 'tingle',
and was soon discharged, but it's surprising what you can find in a
house when you start digging :-)

On 05/05/2020 17:43, Dan S. MacAbre wrote:
newshound wrote:
On 05/05/2020 15:19, Dan S. MacAbre wrote:
Robin wrote:
On 05/05/2020 12:36, Dan S. MacAbre wrote:
I've a question about the earthing connections on our domestic
plumbing. Â*Â*I can see that there is a wire in parallel to our water
meter, but I'm not sure that this can be the main earth because the
supply pipe is plastic.Â* I can also see a wire going into the wall
under the sink, so my assumption here is that it mainly uses the
electrical earth.Â* But there are speedfit connectors under there,
which I expect are not conductive, so there are parts (e.g. pipes
feeding taps) that are isolated from the rest.Â* I'm not worried
about this (although perhaps I should be?), since all this was
supposedly done by professionals; but I thought I'd ask here if
every single section of pipe is meant to be individually earthed,
or if that would not really be practical.Â* Does it even make sense
to earth, for example, braided tap tails?

Your water pipes shouldn't be used to earth your wiring (though they
commonly were in the past).Â* You should have something separate at
your consumer unit/fusebox.


I'm assuming it is the other way around - the mains earth is being
used to earth the water pipes.Â* The wire is coming out of original
plaster (whoever did the kitchen didn't plaster over anything that
wasn't on show), so it has been there since the mid 80's.

What I think you are looking at isÂ* Main Bonding and Supplementary
Bonding. I think you may well be OK on both but suggest you look at

http://wiki.diyfaq.org.uk/index.php/...ng_and_Bonding

and ask again if you still have questions - when people who know
better than me can help.

As for earthing, you can see what things typically look like at

http://wiki.diyfaq.org.uk/index.php/Earthing_Types

If that leaves you with questions about just what you've got it'd
help if you could share [photos somewhere


Thanks for the links.Â* I'll read them, but I'm not going to worry
about what's going on here.

I used to have a kitchen sink that would sometimes give you a tingle.
It didn't after I added bonding, but neither did that trip the RCD. I
never found out what was causing it.

I had a metal light switch that did that.Â* I found that the earthing
wire in the lighting daisy-chain (they hadn't bothered to close the loop
at one of the ends) wasn't connected in one of the roses, which meant
that the rest of them further down the chain weren't earthed.Â* I
measured an induced voltage of 70V on the faceplate.Â* Fixing the
non-connected earth wire solved the problem.Â* It only gave a 'tingle',
and was soon discharged, but it's surprising what you can find in a
house when you start digging :-)

Very true, one house i bought of early 1970's vintage on a large housing
development, had the ring main wired into 2 different fuses in the same
fusebox (yes they were fuses).

I wondered why i couldn't isolate the ring main by withdrawing just the
one fuse.

In converstion later with a next door neighbour he said he had exactly
the same problem!

On 05/05/2020 17:52, Jack Harry Teesdale wrote:

Very true, one house i bought of early 1970's vintage on a large housing
development, had the ring main wired into 2 different fuses in the same
fusebox (yes they were fuses).

I wondered why i couldn't isolate the ring main by withdrawing just the
one fuse.

There was a time that it was not uncommon to join two 15A radial
circuits like this to make a single 30A ring.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 05/05/2020 17:43, Dan S. MacAbre wrote:
newshound wrote:

I used to have a kitchen sink that would sometimes give you a tingle.
It didn't after I added bonding, but neither did that trip the RCD. I
never found out what was causing it.

I had a metal light switch that did that.Â* I found that the earthing
wire in the lighting daisy-chain (they hadn't bothered to close the loop
at one of the ends) wasn't connected in one of the roses, which meant

Lighting circuits are rarely wired as ring, so it would be very unusual
to have the loop closed.

that the rest of them further down the chain weren't earthed.Â* I
measured an induced voltage of 70V on the faceplate.Â* Fixing the
non-connected earth wire solved the problem.Â* It only gave a 'tingle',
and was soon discharged, but it's surprising what you can find in a
house when you start digging :-)

Yup, floating wires can pic up stray induced voltages. IME It only takes
a *tiny* current to pass to let you sense it when you touch. (even if
you don't get a shock or tingle, you can often feel a kind of 50Hz
vibration as you lightly slide your finger tips over the surface of the
metal).

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

John Rumm wrote:
On 05/05/2020 17:43, Dan S. MacAbre wrote:
newshound wrote:

I used to have a kitchen sink that would sometimes give you a tingle.
It didn't after I added bonding, but neither did that trip the RCD. I
never found out what was causing it.

I had a metal light switch that did that.Â* I found that the earthing
wire in the lighting daisy-chain (they hadn't bothered to close the
loop at one of the ends) wasn't connected in one of the roses, which
meant

Lighting circuits are rarely wired as ring, so it would be very unusual
to have the loop closed.


Interesting - I thought it was an oversight.

that the rest of them further down the chain weren't earthed.Â* I
measured an induced voltage of 70V on the faceplate.Â* Fixing the
non-connected earth wire solved the problem.Â* It only gave a 'tingle',
and was soon discharged, but it's surprising what you can find in a
house when you start digging :-)

Yup, floating wires can pic up stray induced voltages. IME It only takes
a *tiny* current to pass to let you sense it when you touch. (even if
you don't get a shock or tingle, you can often feel a kind of 50Hz
vibration as you lightly slide your finger tips over the surface of the
metal).


Yes, it was generally felt when feeling for the switch in the dark. I
sometimes thought it was just the feeling of the brushed-effect metal.
It was only when I measured a voltage there (and it immediately dropped
to zero through the meter) that I decided to do something about it.

On 05/05/2020 21:12, John Rumm wrote:
On 05/05/2020 17:52, Jack Harry Teesdale wrote:

Very true, one house i bought of early 1970's vintage on a large
housing development, had the ring main wired into 2 different fuses in
the same fusebox (yes they were fuses).

I wondered why i couldn't isolate the ring main by withdrawing just
the one fuse.

There was a time that it was not uncommon to join two 15A radial
circuits like this to make a single 30A ring.


I don't think that was the intention in this case. I think it was wired
by an older sparks who didn't really understand the theory of the 30A
ring main.

On 5 May 2020 at 15:16:22 BST, ""Dan S. MacAbre"" wrote:

John Rumm wrote:
On 05/05/2020 12:36, Dan S. MacAbre wrote:

I've a question about the earthing connections on our domestic
plumbing. Â*Â*I can see that there is a wire in parallel to our water
meter, but I'm not sure that this can be the main earth because the
supply pipe is plastic.Â* I can also see a wire going into the wall
under the sink, so my assumption here is that it mainly uses the
electrical earth.Â* But there are speedfit connectors under there,
which I expect are not conductive, so there are parts (e.g. pipes
feeding taps) that are isolated from the rest.Â* I'm not worried about
this (although perhaps I should be?)

Generally nothing to worry about, if all we are discussing is
equipotential bonding.

, since all this was supposedly done by professionals;

Given many of them seem to flounder a little on this particular subject,
that is not always an assurance of anything!


Well, I can tell from some of things I've found that they weren't the
best available.

but I thought I'd ask here if every single section of pipe is meant to
be individually earthed,

Short answer - no.

or if that would not really be practical.Â* Does it even make sense to
earth, for example, braided tap tails?

Not really.

Firstly, this is not about earthing as such, but equipotential bonding -
different things, with different objectives that work in different ways.
However they do often use the same green/yellow insulated wire, and
there are situations where the systems interact.

In its simplest terms, earthing is designed to prevent electrical fires,
and limit the maximum duration of a an electric shock.

Equipotential bonding is designed to limit the magnitude of an electric
shock (i.e. reduce the current that can flow into the victim, by
limiting the voltage (or potential difference) across their body).

EQ bonding is used in places where you are likely to be more
unacceptable to the influence of a shock (e.g. when wet / naked). The
primary question ask when deciding what needs bonding, is "Is this
conductive part actually capable of introducing a potential into the
area". So a length of metal water pipe that comes from elsewhere in the
house to your bath tap, certainly could, and hence needs bonding. A
short section of copper "show work" pipe on the end of a feed in
plastic, does not, since it can't bring a potential in from outside the
zone.

Have a read through this for a fuller explanation:

http://wiki.diyfaq.org.uk/index.php/...ng_and_Bonding


Brilliant. Thanks.

+1. About as close as I'm going to get to understanding :-)
--
Cheers, Rob

On 05/05/2020 17:43, Dan S. MacAbre wrote:

and was soon discharged, but it's surprising what you can find in a
house when you start digging :-)

Especially if you buy Fred West's old house.

--
Adam

On 05/05/2020 12:36, Dan S. MacAbre wrote:
I've a question about the earthing connections on our domestic plumbing.
Â*I can see that there is a wire in parallel to our water meter, but I'm
not sure that this can be the main earth because the supply pipe is
plastic.Â* I can also see a wire going into the wall under the sink, so
my assumption here is that it mainly uses the electrical earth.Â* But
there are speedfit connectors under there, which I expect are not
conductive, so there are parts (e.g. pipes feeding taps) that are
isolated from the rest.Â* I'm not worried about this (although perhaps I
should be?), since all this was supposedly done by professionals; but I
thought I'd ask here if every single section of pipe is meant to be
individually earthed, or if that would not really be practical.Â* Does it
even make sense to earth, for example, braided tap tails?

The idea was not to provide an earth but to tie all exposed metal to be
at the same potential (voltage). Google "equipotential bonding".

However the wiring regulations changed at the beginning of this year and
such things may not be required where there are sections of plastic pipe.

Dave

On Tuesday, 5 May 2020 12:36:53 UTC+1, Dan S. MacAbre wrote:
I've a question about the earthing connections on our domestic plumbing.
I can see that there is a wire in parallel to our water meter, but I'm
not sure that this can be the main earth because the supply pipe is
plastic. I can also see a wire going into the wall under the sink, so
my assumption here is that it mainly uses the electrical earth. But
there are speedfit connectors under there, which I expect are not
conductive, so there are parts (e.g. pipes feeding taps) that are
isolated from the rest. I'm not worried about this (although perhaps I
should be?), since all this was supposedly done by professionals; but I
thought I'd ask here if every single section of pipe is meant to be
individually earthed, or if that would not really be practical. Does it
even make sense to earth, for example, braided tap tails?

What matters is that you've got an effective earth. Is there such a thing from the incomer next to the fusebox? If not, expect to truly need to sort it. If there is then the waterpipe connections are going to only be equipotential bonding, which is a minor safety matter.

NT

On 2020-05-05, John Rumm wrote:

On 05/05/2020 17:43, Dan S. MacAbre wrote:
newshound wrote:

I used to have a kitchen sink that would sometimes give you a tingle.
It didn't after I added bonding, but neither did that trip the RCD. I
never found out what was causing it.

I had a metal light switch that did that.Â* I found that the earthing
wire in the lighting daisy-chain (they hadn't bothered to close the loop
at one of the ends) wasn't connected in one of the roses, which meant

Lighting circuits are rarely wired as ring, so it would be very unusual
to have the loop closed.

that the rest of them further down the chain weren't earthed.Â* I
measured an induced voltage of 70V on the faceplate.Â* Fixing the
non-connected earth wire solved the problem.Â* It only gave a 'tingle',
and was soon discharged, but it's surprising what you can find in a
house when you start digging :-)

Yup, floating wires can pic up stray induced voltages. IME It only takes
a *tiny* current to pass to let you sense it when you touch. (even if
you don't get a shock or tingle, you can often feel a kind of 50Hz
vibration as you lightly slide your finger tips over the surface of the
metal).

I mentioned here a few years ago that in the process of removing an
electric shower, I found my volt stick lighting up at the load end of
the only 10 mm^2 cable, which I was absolutely sure was disconnected
close to the CU. (Of course, I double- & triple-checked.)

The only explanation was current induced from the socket circuit cable
that ran adjacent to the shower cable for several metres.

On 06/05/2020 10:12, wrote:
On Tuesday, 5 May 2020 12:36:53 UTC+1, Dan S. MacAbre wrote:
I've a question about the earthing connections on our domestic plumbing.
I can see that there is a wire in parallel to our water meter, but I'm
not sure that this can be the main earth because the supply pipe is
plastic. I can also see a wire going into the wall under the sink, so
my assumption here is that it mainly uses the electrical earth. But
there are speedfit connectors under there, which I expect are not
conductive, so there are parts (e.g. pipes feeding taps) that are
isolated from the rest. I'm not worried about this (although perhaps I
should be?), since all this was supposedly done by professionals; but I
thought I'd ask here if every single section of pipe is meant to be
individually earthed, or if that would not really be practical. Does it
even make sense to earth, for example, braided tap tails?

What matters is that you've got an effective earth. Is there such a thing from the incomer next to the fusebox? If not, expect to truly need to sort it. If there is then the waterpipe connections are going to only be equipotential bonding, which is a minor safety matter.


If required then the absence of main equipotential bonding is a code 2
on an EICR.


--
Adam

On Wednesday, 6 May 2020 17:48:03 UTC+1, ARW wrote:
On 06/05/2020 10:12, tabbypurr wrote:
On Tuesday, 5 May 2020 12:36:53 UTC+1, Dan S. MacAbre wrote:

I've a question about the earthing connections on our domestic plumbing.
I can see that there is a wire in parallel to our water meter, but I'm
not sure that this can be the main earth because the supply pipe is
plastic. I can also see a wire going into the wall under the sink, so
my assumption here is that it mainly uses the electrical earth. But
there are speedfit connectors under there, which I expect are not
conductive, so there are parts (e.g. pipes feeding taps) that are
isolated from the rest. I'm not worried about this (although perhaps I
should be?), since all this was supposedly done by professionals; but I
thought I'd ask here if every single section of pipe is meant to be
individually earthed, or if that would not really be practical. Does it
even make sense to earth, for example, braided tap tails?

What matters is that you've got an effective earth. Is there such a thing from the incomer next to the fusebox? If not, expect to truly need to sort it. If there is then the waterpipe connections are going to only be equipotential bonding, which is a minor safety matter.


If required then the absence of main equipotential bonding is a code 2
on an EICR.

Yet in terms of actual safety, the benefit is minimal.