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Default Continuity between neutral and earth

Hi All

I have broken into a ring main to extend it to another room. Essentially cutting the return from one socket and then connecting each side of the extended ring to one of the cut ends.

I test the extended ring and it was sound (ie only continuity between the corresponding pairs of wire). I have just connected it to the main ring and did a quick continuity check. Live is ok but it seems that neutral (blue) and earth now have continuity. Given I tested the extended ring it would appear that the original ring suffered this problem. However if this was the case wouldn't the RCd at the MCU have tripped before.

Any ideas?

Thanks

Lee
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leenowell wrote:

Live is ok but it seems that neutral (blue) and earth now have continuity.


Depending on your earthing arrangement, this is probably normal, do you
know type of supply you have?

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

The type determines whether or where your neutral meets earth ...


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Thanks both. Looking at the wiki it looks like it is tn C's.

The incoming wire goes to a fused black box and outbof that comes over neutral and earth. Earth goes to cu and the live and neutral go to the meter and then to the cu via a new isolation switch.
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leenowell wrote:

Looking at the wiki it looks like it is tn C's.
The incoming wire goes to a fused black box and outbof that comes over neutral and earth.


You're *probably* correct, though depending what connections are made
inside the black box (cutout) it could be TNC-S or TN-S, as some of the
photos show (those with/without links from N to E inside the box).

Earth goes to cu and the live and neutral go to the meter and then
to the cu via a new isolation switch.





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The black box has the electric company fuse in it so don't want to take the cover off to check . The incoming cable comes in from the bottom earth comes out to the right and live and neutral out to the too where the fuse is.. In coming is a single black cable.

Does that help in any way. Would both give the symptoms I describe?
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Hi

Yes I think it is TN CS. This picture looks very much like my installation

http://wiki.diyfaq.org.uk/index.php/File:PME1.jpg

So sounds like neutral and earth continuity is correct for my installation.

Thanks for your help

Lee
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Default Continuity between neutral and earth

I was always told that Neutral was supposed to be earth, or almost so.
Otherwise we would have two lives.
Brian

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On Wed, 6 Dec 2017 12:31:30 -0800 (PST),
wrote:

Hi All

I have broken into a ring main to extend it to another room. Essentially
cutting the return from one socket and then connecting each side of the
extended ring to one of the cut ends.

I test the extended ring and it was sound (ie only continuity between the
corresponding pairs of wire). I have just connected it to the main ring
and did a quick continuity check. Live is ok but it seems that neutral
(blue) and earth now have continuity. Given I tested the extended ring it
would appear that the original ring suffered this problem. However if this
was the case wouldn't the RCd at the MCU have tripped before.

Any ideas?


I'm not sure this is the case in every installation but I think the
neutral and earth are connected together somewhere (CU?) and further,
the earth is actually supplied via the neutral on the incoming supply
sometimes?

So, as long as you don't have any N to E [1] or L to E leakage current
on your side of the RCD you should be ok?

Or something like that .. I'm sure someone will be along shortly to
give it to you more accurately. ;-)

Cheers, T i m

[1] Often seen when cutting though a cable even with that cct MCB
switched off.



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On Wednesday, 6 December 2017 20:31:35 UTC, wrote:
Hi All

I have broken into a ring main to extend it to another room. Essentially cutting the return from one socket and then connecting each side of the extended ring to one of the cut ends.

I test the extended ring and it was sound (ie only continuity between the corresponding pairs of wire). I have just connected it to the main ring and did a quick continuity check. Live is ok but it seems that neutral (blue) and earth now have continuity. Given I tested the extended ring it would appear that the original ring suffered this problem. However if this was the case wouldn't the RCd at the MCU have tripped before.

Any ideas?

Thanks

Lee


Neutral and earth are bonded together back at the substation.
It's important that this is the only place they are bonded.
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On 07/12/2017 08:24, wrote:
Hi

Yes I think it is TN CS. This picture looks very much like my installation

http://wiki.diyfaq.org.uk/index.php/File:PME1.jpg

So sounds like neutral and earth continuity is correct for my installation.


N&E continuity (of some sort) is correct for the vast majority of
installations (assuming you are doing the test with the circuit
connected to the CU[1]). With TN-C-S the link is in your property. With
TN-S its back at a substation. With TT its via the general mass of the
earth, and may have a higher resistance, but is still good enough to
make a continuity test "pass" in many cases.


[1] If you want to test your "new" combined circuit in isolation, then
you need to disconnect it at the CU end and test there. That way you
will be free of the influences of the supply itself and any EQ bonding
connections.


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John.

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Default Continuity between neutral and earth

On 07/12/2017 09:44, harry wrote:
On Wednesday, 6 December 2017 20:31:35 UTC, wrote:
Hi All

I have broken into a ring main to extend it to another room. Essentially cutting the return from one socket and then connecting each side of the extended ring to one of the cut ends.

I test the extended ring and it was sound (ie only continuity between the corresponding pairs of wire). I have just connected it to the main ring and did a quick continuity check. Live is ok but it seems that neutral (blue) and earth now have continuity. Given I tested the extended ring it would appear that the original ring suffered this problem. However if this was the case wouldn't the RCd at the MCU have tripped before.

Any ideas?

Thanks

Lee


Neutral and earth are bonded together back at the substation.


That is true.

It's important that this is the only place they are bonded.


That is certainly not true for TN-C-S (PME) supplies which are the
default "standard" for installs these days.

(the clue is in the "M"!)


--
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John.

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Default Continuity between neutral and earth

In article ,
Brian Gaff wrote:
I was always told that Neutral was supposed to be earth, or almost so.
Otherwise we would have two lives.
Brian


It's earth at the substaion, but its volage wrt earth at your home will
depend on how evenly the phases are loaded. 10v wrt earth isn't uncommon.

--
from KT24 in Surrey, England
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Default Continuity between neutral and earth

In article ,
wrote:
I test the extended ring and it was sound (ie only continuity between
the corresponding pairs of wire). I have just connected it to the main
ring and did a quick continuity check. Live is ok but it seems that
neutral (blue) and earth now have continuity. Given I tested the
extended ring it would appear that the original ring suffered this
problem. However if this was the case wouldn't the RCd at the MCU have
tripped before.



Assuming you are testing with the main switch off (double pole) you have a
fault. If testing with only the MCB etc (single pole) off, normal.

--
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Default Continuity between neutral and earth

On Thu, 7 Dec 2017 09:23:40 -0000, "Brian Gaff"
wrote:

I was always told that Neutral was supposed to be earth, or almost so.
Otherwise we would have two lives.
Brian


One of which would then be a negative wouldn't it?

In the past I think some people referred to the black , later blue
wire in domestic wiring as the negative which was wrong but possibly
influenced with tinkering with cars where batteries have a positive
and negative pole, or maybe for old timers it was a hangover from the
days of DC mains.

The yellow 110 volt plugs intended for use with transformers in the UK
to give a 55-0-55 volt supply usaully have both pins identified with a
moulded L rather than an L and an N but I reckon few people using
or even wiring one have noticed.

G.Harman
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Default Continuity between neutral and earth

On Wednesday, 6 December 2017 20:31:35 UTC, wrote:

I have broken into a ring main to extend it to another room. Essentially cutting the return from one socket and then connecting each side of the extended ring to one of the cut ends.

I test the extended ring and it was sound (ie only continuity between the corresponding pairs of wire). I have just connected it to the main ring and did a quick continuity check. Live is ok but it seems that neutral (blue) and earth now have continuity. Given I tested the extended ring it would appear that the original ring suffered this problem. However if this was the case wouldn't the RCd at the MCU have tripped before.


ISTM that a person who does not know that neutral and earth MUST be connected together in at least one place is a person who is not qualified to do such work and the resulting installation is at risk of being in breach of the Building Regulations. See http://www.gutenberg.org/files/27182...-h/27182-h.htm, VI.

--
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Default Continuity between neutral and earth

On Thursday, 7 December 2017 11:10:34 UTC, wrote:
On Thu, 7 Dec 2017 09:23:40 -0000, "Brian Gaff"
wrote:

I was always told that Neutral was supposed to be earth, or almost so.
Otherwise we would have two lives.
Brian


One of which would then be a negative wouldn't it?

In the past I think some people referred to the black , later blue
wire in domestic wiring as the negative which was wrong but possibly
influenced with tinkering with cars where batteries have a positive
and negative pole, or maybe for old timers it was a hangover from the
days of DC mains.

The yellow 110 volt plugs intended for use with transformers in the UK
to give a 55-0-55 volt supply usaully have both pins identified with a
moulded L rather than an L and an N but I reckon few people using
or even wiring one have noticed.

G.Harman


Dc mains used the 2 phase 3 wire system, so half of end users got + and half got -ve dc supplied.


NT
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Default Continuity between neutral and earth

Yes only the MCB was switched off. Rest of the CU was on
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wrote
wrote


I have broken into a ring main to extend it to another room.
Essentially cutting the return from one socket and then
connecting each side of the extended ring to one of the cut ends.


I test the extended ring and it was sound (ie only continuity
between the corresponding pairs of wire). I have just connected
it to the main ring and did a quick continuity check. Live is ok
but it seems that neutral (blue) and earth now have continuity.
Given I tested the extended ring it would appear that the
original ring suffered this problem. However if this was the
case wouldn't the RCd at the MCU have tripped before.


ISTM that a person who does not know that neutral and
earth MUST be connected together in at least one place
is a person who is not qualified to do such work


Thats wrong when the connection is back in the sub station.

and the resulting installation is at risk of being
in breach of the Building Regulations.


Nope.

See http://www.gutenberg.org/files/27182...-h/27182-h.htm, VI.


Irrelevant to your claim.

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Default Continuity between neutral and earth

On Thursday, 7 December 2017 22:21:49 UTC, Rod Speed wrote:
wrote
wrote


I have broken into a ring main to extend it to another room.
Essentially cutting the return from one socket and then
connecting each side of the extended ring to one of the cut ends.


I test the extended ring and it was sound (ie only continuity
between the corresponding pairs of wire). I have just connected
it to the main ring and did a quick continuity check. Live is ok
but it seems that neutral (blue) and earth now have continuity.
Given I tested the extended ring it would appear that the
original ring suffered this problem. However if this was the
case wouldn't the RCd at the MCU have tripped before.


ISTM that a person who does not know that neutral and
earth MUST be connected together in at least one place
is a person who is not qualified to do such work


Thats wrong when the connection is back in the sub station.


You should, before responding, read carefully what has previously been written, and think about it. When neutral and earth are connected together at the sub-station, they are connected together at that place. I did NOT put anything about "connected together within the premises".


and the resulting installation is at risk of being
in breach of the Building Regulations.


Nope.



Yes. A person who does not know that the voltage and the resistance between neutral and earth should each be small is a person who is likely not to know all of the proper safe wiring practices that the Regulations require.


See http://www.gutenberg.org/files/27182...-h/27182-h.htm, VI.


Irrelevant to your claim.


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Default Continuity between neutral and earth

Stop bickering. I mean, its supposed to be earthed, where its earthed only
affects the wiring between that earth and the one that should be down the
line toward the substation, so who really cares?

Brian

--
----- -
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Blind user, so no pictures please!
wrote in message
...
On Thursday, 7 December 2017 22:21:49 UTC, Rod Speed wrote:
wrote
wrote


I have broken into a ring main to extend it to another room.
Essentially cutting the return from one socket and then
connecting each side of the extended ring to one of the cut ends.


I test the extended ring and it was sound (ie only continuity
between the corresponding pairs of wire). I have just connected
it to the main ring and did a quick continuity check. Live is ok
but it seems that neutral (blue) and earth now have continuity.
Given I tested the extended ring it would appear that the
original ring suffered this problem. However if this was the
case wouldn't the RCd at the MCU have tripped before.


ISTM that a person who does not know that neutral and
earth MUST be connected together in at least one place
is a person who is not qualified to do such work


That's wrong when the connection is back in the sub station.


You should, before responding, read carefully what has previously been
written, and think about it. When neutral and earth are connected together
at the sub-station, they are connected together at that place. I did NOT
put anything about "connected together within the premises".


and the resulting installation is at risk of being
in breach of the Building Regulations.


Nope.



Yes. A person who does not know that the voltage and the resistance between
neutral and earth should each be small is a person who is likely not to know
all of the proper safe wiring practices that the Regulations require.


See
http://www.gutenberg.org/files/27182...-h/27182-h.htm, VI.

Irrelevant to your claim.


--
(c) John Stockton, near London, UK. Using Google, no spell-check. |
Mail: - or as Reply-To |


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Default Continuity between neutral and earth

In article ,
Brian Gaff wrote:
Stop bickering. I mean, its supposed to be earthed, where its earthed
only affects the wiring between that earth and the one that should be
down the line toward the substation, so who really cares?


It's not that simple. If you short local earth to neutral here, it will
trip the RCD.

Neutral and earth should only be connected together where they are
designed to be. Which will vary according to your type of mains supply.
With my older installation it isn't done in my house. Presumably at the
local sub station.

--
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Dave Plowman London SW
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On Thursday, 7 December 2017 13:35:22 UTC, John Rumm wrote:
On 07/12/2017 11:20, SL wrote:

ISTM that a person who does not know that neutral and earth MUST be
connected together in at least one place is a person who is not
qualified to do such work and the resulting installation is at risk
of being in breach of the Building Regulations. See


Erroneous statement followed by a non sequitur... Mmmm useful ;-)


The OP reported that connectivity had, to his surprise, been found
between his neutral and earth wires. It is a requirement that the local neutral wires must, somehow, be electrically connected to the terrestrial Earth, and it is a requirement that the local earth wires must, somehow, be electrically connected to the terrestrial Earth. Therefore the reported connectivity is required to exist, and so should be expected; it occurs due to at least one connection, somewhere; such a connection may be man-made metallic or by way of the terrestrial Earth (or by any other reliable means, if any is possible).

--
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On Saturday, 9 December 2017 12:46:05 UTC, wrote:
On Thursday, 7 December 2017 13:35:22 UTC, John Rumm wrote:
On 07/12/2017 11:20, SL wrote:

ISTM that a person who does not know that neutral and earth MUST be
connected together in at least one place is a person who is not
qualified to do such work and the resulting installation is at risk
of being in breach of the Building Regulations. See


Erroneous statement followed by a non sequitur... Mmmm useful ;-)


The OP reported that connectivity had, to his surprise, been found
between his neutral and earth wires. It is a requirement that the local neutral wires must, somehow, be electrically connected to the terrestrial Earth, and it is a requirement that the local earth wires must, somehow, be electrically connected to the terrestrial Earth. Therefore the reported connectivity is required to exist, and so should be expected; it occurs due to at least one connection, somewhere; such a connection may be man-made metallic or by way of the terrestrial Earth (or by any other reliable means, if any is possible).


In fairness I did once see an installation that must have been relying on an extraterrestrial earth


NT
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On 09/12/2017 12:46, wrote:
On Thursday, 7 December 2017 13:35:22 UTC, John Rumm wrote:
On 07/12/2017 11:20, SL wrote:

ISTM that a person who does not know that neutral and earth MUST
be connected together in at least one place is a person who is
not qualified to do such work and the resulting installation is
at risk of being in breach of the Building Regulations. See


Erroneous statement followed by a non sequitur... Mmmm useful ;-)


It is a requirement that the
local neutral wires must, somehow, be electrically connected to the
terrestrial Earth, and it is a requirement that the local earth wires
must, somehow, be electrically connected to the terrestrial Earth.


That is a somewhat different statement from "neutral and earth MUST
be connected together in at least one place". Even then its still
questionable. With a TT supply[1] its fair to assume the neutral will be
connected to earth at the transformer. However that may be the only
place, and there may be no direct connection to the neutral to the
customer's earth.

Their earth should be independently connected to earth locally, however
that may show hundreds of ohms resistance to the earth point on the
supply and hence to the neutral at entry to the premises. (and that
obviously ignores things like IT setups with gensets etc).

[1] Yes, I know the OP does not have one of these, but you made a
blanket statement without qualification.

Therefore the reported connectivity is required to exist, and so


Low impedance connectivity as described by the OP is not *required* to
exist (since it may not be possible), and on TT installs may not.

should be expected; it occurs due to at least one connection,
somewhere; such a connection may be man-made metallic or by way of
the terrestrial Earth (or by any other reliable means, if any is
possible).


Indeed, and that is different from what you said previously.

I also took issue with the assertion that someone not intimately
familiar with earthing systems would not be "qualified" to work on an
electrical system. I have met a number of professionally qualified
electricians that only have a tenuous grasp on such things, but they can
still produce good quality work by applying the rules as specified.

I would assert that its perfectly possible to do a safe and compliant
extension to a socket circuit, and know nothing at all about earthing
systems beyond the need to connect the wires to the socket and test the
continuity when done (as I did many times when I was 12, and would not
have known my earth loop impedance from my elbow!)

The final "at risk of being in breach of the Building Regulations" was a
rather mealy mouthed straw man IMHO. One could argue that everyone is
"at risk" of being in breach of one building regulation or another, but
there was nothing in the OPs post to suggest that was likely here - the
fact that he was asking questions about his observations that obviously
resulted from testing his installation should offer reassurance that
improper work would be much less likely rather than more.

(here endeth the rant about people offering unhelpful criticism in place
of useful advice)


--
Cheers,

John.

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On Thu, 07 Dec 2017 09:51:24 +0000, John Rumm wrote:

On 07/12/2017 08:24, wrote:
Hi

Yes I think it is TN CS. This picture looks very much like my
installation

http://wiki.diyfaq.org.uk/index.php/File:PME1.jpg

So sounds like neutral and earth continuity is correct for my
installation.


N&E continuity (of some sort) is correct for the vast majority of
installations (assuming you are doing the test with the circuit
connected to the CU[1]). With TN-C-S the link is in your property. With
TN-S its back at a substation. With TT its via the general mass of the
earth, and may have a higher resistance, but is still good enough to
make a continuity test "pass" in many cases.


[1] If you want to test your "new" combined circuit in isolation, then
you need to disconnect it at the CU end and test there. That way you
will be free of the influences of the supply itself and any EQ bonding
connections.


This looks to be another advantage of RCBOs.

I had them fitted because I kept knocking the main breaker out with earth/
neutral contact when changing stuff.

Isolating both live and neutral can have advantages when you want to keep
most of the house powered up when you work on one circuit.

Cheers


Dave R



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David wrote:

This looks to be another advantage of RCBOs
Isolating both live and neutral can have advantages when you want to keep
most of the house powered up when you work on one circuit.


Except most RCBOs only break the live pole, the neutral passes through
them, but only for sensing, there are double pole RCBOs but you'd have
to go hunting for them

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On 09/12/2017 12:35, Dave Plowman (News) wrote:
In article ,
Brian Gaff wrote:
Stop bickering. I mean, its supposed to be earthed, where its earthed
only affects the wiring between that earth and the one that should be
down the line toward the substation, so who really cares?


It's not that simple. If you short local earth to neutral here, it will
trip the RCD.

Neutral and earth should only be connected together where they are
designed to be. Which will vary according to your type of mains supply.
With my older installation it isn't done in my house. Presumably at the
local sub station.


If you short Neutral and Earth supply side of the RCD, it should not
trip the RCD.




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On 10/12/2017 14:54, David wrote:
On Thu, 07 Dec 2017 09:51:24 +0000, John Rumm wrote:

On 07/12/2017 08:24, wrote:
Hi

Yes I think it is TN CS. This picture looks very much like my
installation

http://wiki.diyfaq.org.uk/index.php/File:PME1.jpg

So sounds like neutral and earth continuity is correct for my
installation.


N&E continuity (of some sort) is correct for the vast majority of
installations (assuming you are doing the test with the circuit
connected to the CU[1]). With TN-C-S the link is in your property. With
TN-S its back at a substation. With TT its via the general mass of the
earth, and may have a higher resistance, but is still good enough to
make a continuity test "pass" in many cases.


[1] If you want to test your "new" combined circuit in isolation, then
you need to disconnect it at the CU end and test there. That way you
will be free of the influences of the supply itself and any EQ bonding
connections.


This looks to be another advantage of RCBOs.

I had them fitted because I kept knocking the main breaker out with earth/
neutral contact when changing stuff.

Isolating both live and neutral can have advantages when you want to keep
most of the house powered up when you work on one circuit.


Take care with that though since most RCBOs are only single pole
switches (even if they are connected to neutral to allow for current
imbalance sensing). Hence they can't provide isolation of the circuit.


--
Cheers,

John.

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On Thursday, 7 December 2017 22:21:49 UTC, Rod Speed wrote:
wrote
wrote


I have broken into a ring main to extend it to another room.
Essentially cutting the return from one socket and then
connecting each side of the extended ring to one of the cut ends.


I test the extended ring and it was sound (ie only continuity
between the corresponding pairs of wire). I have just connected
it to the main ring and did a quick continuity check. Live is ok
but it seems that neutral (blue) and earth now have continuity.
Given I tested the extended ring it would appear that the
original ring suffered this problem. However if this was the
case wouldn't the RCd at the MCU have tripped before.


ISTM that a person who does not know that neutral and
earth MUST be connected together in at least one place
is a person who is not qualified to do such work


Thats wrong when the connection is back in the sub station.


You should, before responding, read carefully what
has previously been written, and think about it.


Did that, its stays pig ignorant **** no matter
how often its carefully read and thought about.

When neutral and earth are connected together at the
sub-station, they are connected together at that place.


You quite sure you aint actually one of those rocket scientist terminal
****wits ?

I did NOT put anything about "connected together within the premises".


Yes, you were that pig ignorant and stupid.

and the resulting installation is at risk of being
in breach of the Building Regulations.


Nope.


Yes.


Nope.

A person who does not know that the voltage and the resistance
between neutral and earth should each be small


You havent established that he doesnt know that.

is a person who is likely not to know all of the proper
safe wiring practices that the Regulations require.


Even sillier than you usually manage, and thats saying something.

See http://www.gutenberg.org/files/27182...-h/27182-h.htm, VI.


Irrelevant to your claim.



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Default Continuity between neutral and earth

Brian Gaff wrote

Stop bickering.


Get stuffed.

I mean, its supposed to be earthed, where its earthed only affects the
wiring between that earth and the one that should be down the line toward
the substation,


That’s not true of all wiring systems.

so who really cares?


Yep, perfectly safe even if you don’t understand whether
there should be continuity between earth and neutral or not.

wrote in message
...
On Thursday, 7 December 2017 22:21:49 UTC, Rod Speed wrote:
wrote
wrote


I have broken into a ring main to extend it to another room.
Essentially cutting the return from one socket and then
connecting each side of the extended ring to one of the cut ends.


I test the extended ring and it was sound (ie only continuity
between the corresponding pairs of wire). I have just connected
it to the main ring and did a quick continuity check. Live is ok
but it seems that neutral (blue) and earth now have continuity.
Given I tested the extended ring it would appear that the
original ring suffered this problem. However if this was the
case wouldn't the RCd at the MCU have tripped before.


ISTM that a person who does not know that neutral and
earth MUST be connected together in at least one place
is a person who is not qualified to do such work


That's wrong when the connection is back in the sub station.


You should, before responding, read carefully what has previously been
written, and think about it. When neutral and earth are connected
together at the sub-station, they are connected together at that place. I
did NOT put anything about "connected together within the premises".


and the resulting installation is at risk of being
in breach of the Building Regulations.


Nope.



Yes. A person who does not know that the voltage and the resistance
between neutral and earth should each be small is a person who is likely
not to know all of the proper safe wiring practices that the Regulations
require.


See http://www.gutenberg.org/files/27182...-h/27182-h.htm, VI.


Irrelevant to your claim.


--
(c) John Stockton, near London, UK. Using Google, no spell-check. |
Mail: - or as Reply-To |

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Default Continuity between neutral and earth



wrote in message
...
On Thursday, 7 December 2017 13:35:22 UTC, John Rumm wrote:
On 07/12/2017 11:20, SL wrote:

ISTM that a person who does not know that neutral and earth MUST be
connected together in at least one place is a person who is not
qualified to do such work and the resulting installation is at risk
of being in breach of the Building Regulations. See


Erroneous statement followed by a non sequitur... Mmmm useful ;-)


The OP reported that connectivity had, to his surprise, been found
between his neutral and earth wires. It is a requirement that the
local neutral wires must, somehow, be electrically connected to
the terrestrial Earth, and it is a requirement that the local earth
wires must, somehow, be electrically connected to the terrestrial
Earth. Therefore the reported connectivity is required to exist,
and so should be expected; it occurs due to at least one
connection, somewhere; such a connection may be man-
made metallic or by way of the terrestrial Earth (or by
any other reliable means, if any is possible).


Yes, but when breaking into a ring to add something, he doesnt need
to know about the required connection between earth and neutral to
do that safely. In spades when it happens back in the sub station.

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Default Continuity between neutral and earth

In article ,
Fredxx wrote:
On 09/12/2017 12:35, Dave Plowman (News) wrote:
In article ,
Brian Gaff wrote:
Stop bickering. I mean, its supposed to be earthed, where its earthed
only affects the wiring between that earth and the one that should be
down the line toward the substation, so who really cares?


It's not that simple. If you short local earth to neutral here, it will
trip the RCD.

Neutral and earth should only be connected together where they are
designed to be. Which will vary according to your type of mains supply.
With my older installation it isn't done in my house. Presumably at the
local sub station.


If you short Neutral and Earth supply side of the RCD, it should not
trip the RCD.


No **** sherlock? Why would anyone actually do that when fitting a new
socket, etc?

--
*Why is the man who invests all your money called a broker?

Dave Plowman London SW
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