Replaced a garage consumer unit in my SILs shed last weekend.

Easy enough because we could kill the breaker in the house.

But I wondered, how is it done if you change the CU in a house?

There isn't an outside 'stopcock' for electricity.

Is it done 'live'?


--
Dave - The Medway Handyman www.medwayhandyman.co.uk

The Medway Handyman wrote:

how is it done if you change the CU in a house?
There isn't an outside 'stopcock' for electricity.

It's not uncommon to have a two-pole isolator between the meter and the CU.

Is it done 'live'?

No, if there's no isolator, the main fuse in the cut-out before the
meter would be pulled (officially or otherwise) at that point it's a
good idea to fit an isolator.

In article ,
The Medway Handyman wrote:
Replaced a garage consumer unit in my SILs shed last weekend.

Easy enough because we could kill the breaker in the house.

But I wondered, how is it done if you change the CU in a house?

There isn't an outside 'stopcock' for electricity.

Is it done 'live'?

You pull the main fuse on the riser.

--
*A bartender is just a pharmacist with a limited inventory.

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

On 03/08/14 09:36, The Medway Handyman wrote:
Replaced a garage consumer unit in my SILs shed last weekend.

Easy enough because we could kill the breaker in the house.

But I wondered, how is it done if you change the CU in a house?

There isn't an outside 'stopcock' for electricity.

Is it done 'live'?



5 ways:

1) Pull the cutout fuse;

2) Disconnect CU tails from henley block if you have one;

3) Work live;

4) Operate main isolator if fitted;

5) Operate meter's built in isolator if the right type.


1 - EDF charged me 35 squid to pull and refit the fuse - they took all
day to come back. This would be the most painful way, but arguable the
"correct" way in the absence of other options. My seals were newish.

If the seals are broken or are not new looking, they might "fall off"
allowing you to pull the fuse. HOWEVER be warned that old and flaky
cutouts fed by paper insulated cable dating to 1940 show never be
touched as a) The cutout may break up in your hands or b) the cutout
comes off the wall, bends the now brittle and dried out cable and it
dumps a short circuits worth of metal plasma in your face.

2) Technical working live, but with the right tools, good access and
done carefully is not particularly dangerous. I have done this. I do not
recommend anyone else does.

3) The most dangerous option - so much as to be a non option for anyone
who is sensible. It is probably done sometimes. But there is no need.

4) Some supply companies do fit these. I fitted my own. EDF were not
hugely keen but they put up with it anyway.

5) Do check - certain makes/models of meter do have an isolator built in
- some Siemens types.

"Tim Watts" wrote in message
...
On 03/08/14 09:36, The Medway Handyman wrote:

5) Do check - certain makes/models of meter do have an isolator built in -
some Siemens types.


You still have to cut the seals on the meter to access the isolatior switch.

--
Adam

On Sun, 03 Aug 2014 10:02:23 +0100, Tim Watts wrote:

2) Technical working live, but with the right tools, good access and
done carefully is not particularly dangerous. I have done this. I do not
recommend anyone else does.

3) The most dangerous option - so much as to be a non option for anyone
who is sensible. It is probably done sometimes. But there is no need.

But isn't 2 "working live" as the henley block terminals are live?
Admitedly you then have dead tails to work with rather than live bare
ended live ones waving about.

--
Cheers
Dave.

On Sun, 03 Aug 2014 09:50:57 +0100, Dave Plowman (News) wrote:

You pull the main fuse on the riser.

Incomer, risers are water. B-)

--
Cheers
Dave.

On Sun, 03 Aug 2014 09:44:33 +0100, Tim Streater wrote:

Isn't there a main breaker you turn off?

Most installations have that as part of the CU that is being
changed...

No one has mentioned the pole fuse outside. Ours was only about 8'
off the ground until they came round replaced it, the stays and
capping over the earth bonding etc. It's now about 16' above the
ground. It only feeds us so pulling that wouldn't cut anybody else
off.

--
Cheers
Dave.

The Medway Handyman wrote

Replaced a garage consumer unit in my SILs shed last weekend.

Easy enough because we could kill the breaker in the house.

But I wondered, how is it done if you change the CU in a house?

There isn't an outside 'stopcock' for electricity.

There is actually, the fuses on the mains supply. Just pull them.

Is it done 'live'?

Nope.

On 03/08/14 10:05, ARW wrote:
"Tim Watts" wrote in message
...
On 03/08/14 09:36, The Medway Handyman wrote:

5) Do check - certain makes/models of meter do have an isolator built
in - some Siemens types.


You still have to cut the seals on the meter to access the isolatior
switch.


Really? Seems stupid... And somewhat pointless. Undoing 2 screws live to
remove the CU tails is not hugely risky.

I also read somewhere that the new smart meters will not have isolators
either...

"Dave Liquorice" wrote in message
ll.co.uk...
On Sun, 03 Aug 2014 09:50:57 +0100, Dave Plowman (News) wrote:

You pull the main fuse on the riser.

Incomer, risers are water. B-)


Or a cut out.

http://www.thefusecompany.com/fuses/...cut-out-units/

I have heard the term dry riser used for electrical supplies in flats. It's
not a name I would use.

--
Adam

On 03/08/14 11:05, Dave Liquorice wrote:
On Sun, 03 Aug 2014 10:02:23 +0100, Tim Watts wrote:

2) Technical working live, but with the right tools, good access and
done carefully is not particularly dangerous. I have done this. I do not
recommend anyone else does.

3) The most dangerous option - so much as to be a non option for anyone
who is sensible. It is probably done sometimes. But there is no need.

But isn't 2 "working live" as the henley block terminals are live?
Admitedly you then have dead tails to work with rather than live bare
ended live ones waving about.



Yes - I was going to footnote that but forgot.

You said exactly what I was going to.

Live working on something fixed does not bother me. Having a live bare
ended wire flapping around does.

En el artículo , ARW adamwadsworth@blueyond
er.co.uk escribió:

I have heard the term dry riser used for electrical supplies in flats. It's
not a name I would use.

I thought the term 'dry riser' referred to a hollow vertical shaft in
multiple-storey buildings used to carry services such as gas, water,
power, drainage, telecomms, etc.

--
(\_/)
(='.'=)
(")_(")

"Mike Tomlinson" wrote in message
...
En el artículo , ARW adamwadsworth@blueyond
er.co.uk escribió:

I have heard the term dry riser used for electrical supplies in flats.
It's
not a name I would use.

I thought the term 'dry riser' referred to a hollow vertical shaft in
multiple-storey buildings used to carry services such as gas, water,
power, drainage, telecomms, etc.


That is where I have head the term used. However the water supplies would be
in a wet riser (IMHO) and things get more complicated in high rise flats
where there are dry riser pipes intended for use by fire fighters.


--
Adam

On 03/08/2014 11:05, Dave Liquorice wrote:
On Sun, 03 Aug 2014 10:02:23 +0100, Tim Watts wrote:

2) Technical working live, but with the right tools, good access and
done carefully is not particularly dangerous. I have done this. I do not
recommend anyone else does.

3) The most dangerous option - so much as to be a non option for anyone
who is sensible. It is probably done sometimes. But there is no need.

But isn't 2 "working live" as the henley block terminals are live?
Admitedly you then have dead tails to work with rather than live bare
ended live ones waving about.


Just screw them into spare henley blocks or the isolator you are going
to fit.

Tim Watts wrote:

I also read somewhere that the new smart meters will not have isolators
either...

Well they contain a contactor that can disconnect the supply. Even if
they offered a facility for you to call them and arrange a temporary
disconnection, would you trust it not to reconnect when you least
expected it?

"ARW" wrote in
:

"Mike Tomlinson" wrote in message
...
En el artículo , ARW
adamwadsworth@blueyond er.co.uk escribió:

I have heard the term dry riser used for electrical supplies in
flats. It's
not a name I would use.

I thought the term 'dry riser' referred to a hollow vertical shaft in
multiple-storey buildings used to carry services such as gas, water,
power, drainage, telecomms, etc.


That is where I have head the term used. However the water supplies
would be in a wet riser (IMHO) and things get more complicated in high
rise flats where there are dry riser pipes intended for use by fire
fighters.



Dry Riser is used by the fire service in the event of fires in the
building. As it is kept dry it cannot freeze.

In article o.uk,
Dave Liquorice wrote:
On Sun, 03 Aug 2014 09:50:57 +0100, Dave Plowman (News) wrote:

You pull the main fuse on the riser.

Incomer, risers are water. B-)

We'll get on to pattress in a minute. ;-)

--
*Also too, never, ever use repetitive redundancies *

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

On 03/08/14 09:36, The Medway Handyman wrote:
Replaced a garage consumer unit in my SILs shed last weekend.

Easy enough because we could kill the breaker in the house.

But I wondered, how is it done if you change the CU in a house?

There isn't an outside 'stopcock' for electricity.

Ther is. At the local substation

Is it done 'live'?

Often, yes




--
Everything you read in newspapers is absolutely true, except for the
rare story of which you happen to have first-hand knowledge. €“ Erwin Knoll

..
If the seals are broken or are not new looking, they might "fall off"
allowing you to pull the fuse. HOWEVER be warned that old and flaky
cutouts fed by paper insulated cable dating to 1940 show never be
touched as a) The cutout may break up in your hands or b) the cutout
comes off the wall, bends the now brittle and dried out cable and it
dumps a short circuits worth of metal plasma in your face.

Just how old are some of the incomer cables now?. A house that I own was
built in 1890 and the power was initially put in appx 1925 "ish".

I don't think anyone's altered the incomer cable since then it does look
very olde so just how old are they allowed to be before they are
replaced or do they wait till it all just goes Bang! One day and change
it then?..

Anyone know?....
--
Tony Sayer

On 03/08/2014 09:36, The Medway Handyman wrote:
Replaced a garage consumer unit in my SILs shed last weekend.

Easy enough because we could kill the breaker in the house.

But I wondered, how is it done if you change the CU in a house?

http://wiki.diyfaq.org.uk/index.php?...ting_the_power

There isn't an outside 'stopcock' for electricity.

Sometimes there is ;-)

Is it done 'live'?

Also sometimes done.

--
Cheers,

John.

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

On 03/08/2014 11:36, Tim Watts wrote:
On 03/08/14 11:05, Dave Liquorice wrote:
On Sun, 03 Aug 2014 10:02:23 +0100, Tim Watts wrote:

2) Technical working live, but with the right tools, good access and
done carefully is not particularly dangerous. I have done this. I do not
recommend anyone else does.

3) The most dangerous option - so much as to be a non option for anyone
who is sensible. It is probably done sometimes. But there is no need.

But isn't 2 "working live" as the henley block terminals are live?
Admitedly you then have dead tails to work with rather than live bare
ended live ones waving about.



Yes - I was going to footnote that but forgot.

You said exactly what I was going to.

Live working on something fixed does not bother me. Having a live bare
ended wire flapping around does.

I replaced a secondary extra CU once where the main cutout was decidedly
dodgy looking. So opted to disconnect the tails to the CU in question at
the henley. Its very minimal live working since once the tails are free,
they are not live and you can stick the lid back on the henley.

The only challenge with that one was the henley had allen headed screws,
and I don't have any VDE allen keys. So I used a hex bit in a mag holder
cocooned in insulating tape, and stuck it in my cordless drill.

--
Cheers,

John.

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

On 03/08/2014 13:55, tony sayer wrote:

Just how old are some of the incomer cables now?. A house that I own was
built in 1890 and the power was initially put in appx 1925 "ish".

Incomer cable here is the old lead/bitumen from when the place was
built. Originally had a cast iron fuse/cutout but the 'board replaced
that with a modern plastic one a few years ago and said the cable was
"fine".

Wasn't there a discussion in here some time ago that concluded that
these old cable were actually safer than they appeared due to the
failure mode being somewhat "gentle"?
Or was I imagining that?

"John Rumm" wrote in message
...
On 03/08/2014 11:36, Tim Watts wrote:
On 03/08/14 11:05, Dave Liquorice wrote:
On Sun, 03 Aug 2014 10:02:23 +0100, Tim Watts wrote:

2) Technical working live, but with the right tools, good access and
done carefully is not particularly dangerous. I have done this. I do
not
recommend anyone else does.

3) The most dangerous option - so much as to be a non option for anyone
who is sensible. It is probably done sometimes. But there is no need.

But isn't 2 "working live" as the henley block terminals are live?
Admitedly you then have dead tails to work with rather than live bare
ended live ones waving about.



Yes - I was going to footnote that but forgot.

You said exactly what I was going to.

Live working on something fixed does not bother me. Having a live bare
ended wire flapping around does.

I replaced a secondary extra CU once where the main cutout was decidedly
dodgy looking. So opted to disconnect the tails to the CU in question at
the henley. Its very minimal live working since once the tails are free,
they are not live and you can stick the lid back on the henley.

The only challenge with that one was the henley had allen headed screws,
and I don't have any VDE allen keys. So I used a hex bit in a mag holder
cocooned in insulating tape, and stuck it in my cordless drill.


Nothing wrong with that.
--
Adam

1 - EDF charged me 35 squid to pull and refit the fuse - they took all
day to come back. This would be the most painful way, but arguable the
"correct" way in the absence of other options. My seals were newish.

FWIW in September 2012 a BG customer could get an isolator fitted for
less than that - GBP 31.42 to be precise. Might be worth anyone facing
the same need asking their supplier if they offer a similar deal.

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

On 03/08/14 15:04, Robin wrote:
1 - EDF charged me 35 squid to pull and refit the fuse - they took all
day to come back. This would be the most painful way, but arguable the
"correct" way in the absence of other options. My seals were newish.

FWIW in September 2012 a BG customer could get an isolator fitted for
less than that - GBP 31.42 to be precise. Might be worth anyone facing
the same need asking their supplier if they offer a similar deal.


I did and EDF did not even have an option. I doubt UK Power who bought
the southern network are and different.

Some other suppliers do though.

I did and EDF did not even have an option. I doubt UK Power who bought
the southern network are and different.

This was for a BG customer in London so IIRC EDF were (then) the DNO.
And just to add to the confusion when Scottish Power were the supplier
in 2011 they said they couldn't provide an isolator at all. How the
supplier comes into it is all too difficult fo rme.

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

On 03/08/2014 09:50, Dave Plowman (News) wrote:
In article ,
The Medway Handyman wrote:
Replaced a garage consumer unit in my SILs shed last weekend.

Easy enough because we could kill the breaker in the house.

But I wondered, how is it done if you change the CU in a house?

There isn't an outside 'stopcock' for electricity.

Is it done 'live'?

You pull the main fuse on the riser.

After I rewired my first house, the SWEB guys just connected my tails to
the distribution point "live". These days, "Oh the seal wires on the
main fuse seem to be broken".

On Sun, 3 Aug 2014 16:37:09 +0100, Robin wrote:

This was for a BG customer in London so IIRC EDF were (then) the DNO.
And just to add to the confusion when Scottish Power were the supplier
in 2011 they said they couldn't provide an isolator at all. How the
supplier comes into it is all too difficult fo rme.

It's very simple:

Every thing before and including the main cutout and main earth
terminal is the DNO's responsibilty.

The connections from cutout to metering equipment and the meter(s) is
the responsibilty of who ever you buy your electricity from.

Everything past the meter output terminals and the MET is the
responsibilty of the householder.

So an isolator is really the householders kit but of course one needs
a bit of care to install it or pulling the cut out or breaking the
seal on the meter to change the tails.

--
Cheers
Dave.

On 03/08/14 16:37, Robin wrote:
I did and EDF did not even have an option. I doubt UK Power who bought
the southern network are and different.

This was for a BG customer in London so IIRC EDF were (then) the DNO.
And just to add to the confusion when Scottish Power were the supplier
in 2011 they said they couldn't provide an isolator at all. How the
supplier comes into it is all too difficult fo rme.


Just to clarify - I am in the SEEBOARD area...

It's very simple:

Well it is now, thanks

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

On Sunday, August 3, 2014 9:36:17 AM UTC+1, The Medway Handyman wrote:
But I wondered, how is it done if you change the CU in a house?

Apparently, if you're an approved electrician in the Scottish Power area, you can get a supply of numbered paper seals and obtain permission telephonically for each address as which you want to unseal the cutout. You then reseal it with the paper seal and SP go round sometime later and reseal properly.

Owain

On Sun, 03 Aug 2014 12:30:34 +0100, Dave Plowman (News) wrote:

In article o.uk,
Dave Liquorice wrote:
On Sun, 03 Aug 2014 09:50:57 +0100, Dave Plowman (News) wrote:

You pull the main fuse on the riser.

Incomer, risers are water. B-)

We'll get on to pattress in a minute. ;-)

Foam or spring?
--
Peter.
The gods will stay away
whilst religions hold sway

On 03/08/2014 19:17, Tim Watts wrote:
On 03/08/14 16:37, Robin wrote:
I did and EDF did not even have an option. I doubt UK Power who bought
the southern network are and different.

This was for a BG customer in London so IIRC EDF were (then) the DNO.
And just to add to the confusion when Scottish Power were the supplier
in 2011 they said they couldn't provide an isolator at all. How the
supplier comes into it is all too difficult fo rme.


Just to clarify - I am in the SEEBOARD area...

When I worked for Seeboard, in the days when it was a nationalised
industry, the view was that they didn't want domestic consumers to have
an isolator before the CU. On request the Board would come and pull the
main fuses and replace them later, all free of charge. It was seen as a
way of ensuring that a Board employee would get to look over any major
changes before reconnecting to the supply. If meter readers saw broken
seals on the fuses, that would get passed back and an electrician would
usually be sent out to reseal the fuse, have a word with the occupier
and look over the system.

--
Colin Bignell

On 04/08/14 07:35, Nightjar "cpb"@ insert my surname here wrote:
On 03/08/2014 19:17, Tim Watts wrote:
On 03/08/14 16:37, Robin wrote:
I did and EDF did not even have an option. I doubt UK Power who bought
the southern network are and different.

This was for a BG customer in London so IIRC EDF were (then) the DNO.
And just to add to the confusion when Scottish Power were the supplier
in 2011 they said they couldn't provide an isolator at all. How the
supplier comes into it is all too difficult fo rme.


Just to clarify - I am in the SEEBOARD area...

When I worked for Seeboard, in the days when it was a nationalised
industry, the view was that they didn't want domestic consumers to have
an isolator before the CU. On request the Board would come and pull the
main fuses and replace them later, all free of charge. It was seen as a
way of ensuring that a Board employee would get to look over any major
changes before reconnecting to the supply. If meter readers saw broken
seals on the fuses, that would get passed back and an electrician would
usually be sent out to reseal the fuse, have a word with the occupier
and look over the system.


The guy who came to me wanted to see my CU and check the polarity.

He also wanted my NICEIC number. He seemed bemused when I said the job
was lodged with the LABC.

The fact I'd spent quite some time making the cable runs look pretty
helped as he left with a compliment that it was "better than many jobs
he'd seen".

But now I have my own isolator...

Tim Watts wrote:

The guy who came to me wanted to see my CU and check the polarity.
But now I have my own isolator...

I asked the DNO and supplier if they would fit an isolator, or could
permit me to pull the fuse and task the meter reader with re-sealing it
on next visit ... each said ""no" and to ask the other.

So I cut the seal, pulled the fuse, changed the 16mm^2 tails for 25mm^2,
fitted my own isolator (on "their" board tsk-tsk) and replaced the CU,
it sat there unsealed for ~8 years, unquestioned by any meter readers.
When they came to fit smart meters, the chap did notice the improved
tails, so uprated me from 60A to 100A fuse, he checked polarity with an
el-cheapo plugin neon tester, but that was the extent of any inspection.

wrote:

Apparently, if you're an approved electrician in the Scottish Power area,
you can get a supply of numbered paper seals and obtain permission
telephonically for each address as which you want to unseal the cutout.
You then reseal it with the paper seal and SP go round sometime later and
reseal properly.

Scottish Power were less fussy when they changed the meter here. The guy
broke off the plastic lugs for the seals so now there's no way of sealing
the main fuse. That was about 5 years ago so things might have changed since
then but the meter readers have never commented about the lack of seals.

--
Mike Clarke

On Sun, 03 Aug 2014 11:35:36 +0100, Tim Watts
wrote:


I also read somewhere that the new smart meters will not have isolators
either...

When my smart meter was installed in May the existing isolator was
retained, and carefully re-sealed - the seals had been broken when the
solar panels were installed a couple of years ago.

On Mon, 4 Aug 2014 07:18:46 +0100, PeterC wrote:

Incomer, risers are water. B-)

We'll get on to pattress in a minute. ;-)

Foam or spring?

Sqornshellian.

--
Cheers
Dave.

In message , PeterC
writes
On Sun, 03 Aug 2014 12:30:34 +0100, Dave Plowman (News) wrote:

In article o.uk,
Dave Liquorice wrote:
On Sun, 03 Aug 2014 09:50:57 +0100, Dave Plowman (News) wrote:

You pull the main fuse on the riser.

Incomer, risers are water. B-)

We'll get on to pattress in a minute. ;-)

Foam or spring?
From memory - foam
--
bert