This morning (prior to fitting a replacement lightswitch), whilst polyfilling a small section of a wall - I forgot to switch off the electrics and managed to have the live wire touch the earth wire

The MCB tripped for the downstairs light circuit (as it should) but after resetting the MCB - it reset easily - I have lost all the lights downstairs - there is no current going through at all. All the other circuits are fine in the house.

What could the matter be? Can anyone help please?

Thanks

On 18 Mar, 21:06, eastangliacyclist eastangliacyclist.
wrote:

This morning (prior to fitting a replacement lightswitch), whilst
polyfilling a small section of a wall - I forgot to switch off the
electrics and managed to have the live wire touch the earth wire

The MCB tripped for the downstairs light circuit (as it should) but
after resetting the MCB - it reset easily - I have lost all the lights
downstairs - there is no current going through at all. All the other
circuits are fine in the house.

What could the matter be? Can anyone help please?

Thanks


something somewhere burnt out due to the current surge. Lightswitches
are vulnerable to this.


NT

wrote in message
ups.com...
On 18 Mar, 21:06, eastangliacyclist eastangliacyclist.
wrote:

This morning (prior to fitting a replacement lightswitch), whilst
polyfilling a small section of a wall - I forgot to switch off the
electrics and managed to have the live wire touch the earth wire

The MCB tripped for the downstairs light circuit (as it should)
but
after resetting the MCB - it reset easily - I have lost all the
lights
downstairs - there is no current going through at all. All the
other
circuits are fine in the house.

What could the matter be? Can anyone help please?

Thanks


something somewhere burnt out due to the current surge.
Lightswitches
are vulnerable to this.


NT


Or maybe the MCB died electrically despite apparently resetting?

AWEM

eastangliacyclist wrote:

This morning (prior to fitting a replacement lightswitch), whilst
polyfilling a small section of a wall - I forgot to switch off the
electrics and managed to have the live wire touch the earth wire

The MCB tripped for the downstairs light circuit (as it should) but
after resetting the MCB - it reset easily - I have lost all the lights
downstairs - there is no current going through at all. All the other
circuits are fine in the house.

What could the matter be? Can anyone help please?

Is the light switch you were working on likely to be the first light on
the circuit? If it is not then that makes it less likely (although not
impossible) that it is a wiring related failure.

It is possible that the MCB has failed. To be certain you would need to
take the cover off the CU and test the output terminal with a volt meter
to make sure it is electrically "on" when it ought to be.

--
Cheers,

John.

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

On 18 Mar, 23:02, "Andrew Mawson"
wrote:
wrote in message
ups.com...
On 18 Mar, 21:06, eastangliacyclist eastangliacyclist.
wrote:

This morning (prior to fitting a replacement lightswitch), whilst
polyfilling a small section of a wall - I forgot to switch off the
electrics and managed to have the live wire touch the earth wire

The MCB tripped for the downstairs light circuit (as it should)
but
after resetting the MCB - it reset easily - I have lost all the
lights
downstairs - there is no current going through at all. All the
other
circuits are fine in the house.

What could the matter be? Can anyone help please?

Thanks

something somewhere burnt out due to the current surge.
Lightswitches
are vulnerable to this.

NT

Or maybe the MCB died electrically despite apparently resetting?

AWEM

Best use a multimeter to find the fault.


NT

Hi, Thanks for all the advice.

The lightswitch is right at the end of the house - in the utility room - so not at the start of the circuit. I have also swapped the MCB with a different one (in case it was damaged) and still no current.

I guess that something has burnt out somewhere - I'll keep you informed of progress.

Thanks
EAC

eastangliacyclist wrote:

The lightswitch is right at the end of the house - in the utility room
- so not at the start of the circuit. I have also swapped the MCB with
a different one (in case it was damaged) and still no current.

If you are sure you have tried all the lights on that circuit and none
of them work, then try and identify the first light on the circuit.
Check to see if power is reaching its ceiling rose. There is a
reasonable chance that will be where your problem is.



--
Cheers,

John.

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

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

The lightswitch is right at the end of the house - in the utility
room
- so not at the start of the circuit. I have also swapped the MCB
with
a different one (in case it was damaged) and still no current.

If you are sure you have tried all the lights on that circuit and
none
of them work, then try and identify the first light on the circuit.
Check to see if power is reaching its ceiling rose. There is a
reasonable chance that will be where your problem is.



--
Cheers,

John.

Now John, you KNOW the broken wire is ALWAYS in the least accessable
position !

AWEM

On Mon, 19 Mar 2007 11:22:35 +0000 someone who may be
eastangliacyclist wrote
this:-

The lightswitch is right at the end of the house - in the utility room
- so not at the start of the circuit.

How do you know?

I have also swapped the MCB with
a different one (in case it was damaged) and still no current.

How do you know? Have you measured the voltage?



--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

Andrew Mawson wrote:

Now John, you KNOW the broken wire is ALWAYS in the least accessable
position !

and the last place you look....

(then again, to carry on looking once you had found it would suggest a
"special" type of intelligence! ;-)

--
Cheers,

John.

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

In message . com,
writes
Or maybe the MCB died electrically despite apparently resetting?

AWEM

Best use a multimeter to find the fault.

Best use a properly designed set of testlamps to find the fault.
Domestic multimeters in the wrong hands can become bombs when they are
inadvertently applied to mains voltage while the leads are in the 10A
sockets.

That's why many meters now don't have a 10A AC setting. (I think it's a
liability thing.)

Industrial test meters have a good quality HRC fuse in series with the
10A range to break the circuit in a controlled manner.

--
Clive Mitchell
http://www.bigclive.com

On 19 Mar, 23:27, Clive Mitchell wrote:
In message . com,
writes

Best use a multimeter to find the fault.

Best use a properly designed set of testlamps to find the fault.
Domestic multimeters in the wrong hands can become bombs when they are
inadvertently applied to mains voltage while the leads are in the 10A
sockets.

That's why many meters now don't have a 10A AC setting. (I think it's a
liability thing.)

Industrial test meters have a good quality HRC fuse in series with the
10A range to break the circuit in a controlled manner.

6A mcb not good enough?

There are other risks too, such as touching one prod while poking the
other... one needs some competence when dealing with situations with
inherent risks. And ideally the meter would be cat whichever it is
etc.


NT

In message .com,
writes
That's why many meters now don't have a 10A AC setting. (I think it's a
liability thing.)

Industrial test meters have a good quality HRC fuse in series with the
10A range to break the circuit in a controlled manner.

6A mcb not good enough?

Not if you poke the meter on the supply side.

The REALLY nasty accidents with cheap meters happen on industrial
supplies.

--
Clive Mitchell
http://www.bigclive.com

"Clive Mitchell" wrote in message
...
In message .com,
writes
That's why many meters now don't have a 10A AC setting. (I think it's a
liability thing.)

Industrial test meters have a good quality HRC fuse in series with the
10A range to break the circuit in a controlled manner.

6A mcb not good enough?

Not if you poke the meter on the supply side.

The REALLY nasty accidents with cheap meters happen on industrial
supplies.

--
Clive Mitchell
http://www.bigclive.com

May I point you all in the direction of
http://fluke.informationstore.net/ef...tion=10046-eng
and suggest if you want to prod round a consumer unit then you do need a
good safe DVM such as some of the modern Flukes or the Meterman range.

NB there is a cheap DVM that is on sale at some DIY stores, this has a 10A
range that on the sample that I recived was proctected by a glass 10A
fuse....

In message , James Salisbury
writes
NB there is a cheap DVM that is on sale at some DIY stores, this has a
10A range that on the sample that I recived was proctected by a glass
10A fuse....

Which is as good as no protection, since the glass fuses arc internally
through the metal vapour from the exploded fuse, failing to break the
circuit in a controlled manner and adding to the final explosion.

Like this one....
http://www.emanator.demon.co.uk/glass.jpg

--
Clive Mitchell
http://www.bigclive.com

Clive Mitchell wrote:

Industrial test meters have a good quality HRC fuse in series with the
10A range to break the circuit in a controlled manner.


Is it just me who doesn't like actually holding a dmm when measuring
mains or higher voltages?
Since it has a stand anyway, I usually put it down on a surface or hang
it when using it.
It does have a 20A Bussmann HRC fuse, (and a 5A for the lower ranges)
but I would still not want to be holding it if I'd inadvertently stuck
the probes in the "Amp" sockets while checking mains voltage

Lee
--
Email address is valid, but is unlikely to be read.