Do I need to update my house's fuse box?

Jim x321x

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Jun 21, 2015, 6:20:25 PM6/21/15

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My house was built and wired in the 1980s and has an old-style fuse box.
The old fuses have all been repeplaced with cirquit-breakers plugged into
the fuse sockets. A couple of people, such as estate agents and
electricians have raised eyebrows on seeing the box, telling me it should
be changed for a modern RCD unit. Is this true? I've never had any problems
with the existing setup, and I rarely get any inexplicable tripping of the
circuit breakers. As far as I am aware, the old fuse boxes (even when fuses
contained fuse wire) did what they were designed to do, with no problems.

My fuse box has circuit-breakers for:
Upstairs ring main
Downstairs ring main
Upstairs light circuit
Downstairs lighting circuit
Electric shower circuit
External security lights circuit

Obviously, I'd like to avoid the expense of updating it if I'm not under
any legal obligation to change anything. Is there really a significant
increase in electrical safety with the modern RCD units?

What about if I rent the house to tenants? Will it then need to comply with
the latest electrical regulation specs?

THanks for some help.

Jim

tabb...@gmail.com

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Jun 21, 2015, 11:14:05 PM6/21/15

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On Sunday, 21 June 2015 23:20:25 UTC+1, Jim x321x wrote:
> My house was built and wired in the 1980s and has an old-style fuse box.

then no, in most cases

> The old fuses have all been repeplaced with cirquit-breakers plugged into
> the fuse sockets. A couple of people, such as estate agents and
> electricians have raised eyebrows on seeing the box, telling me it should
> be changed for a modern RCD unit. Is this true?

no

> I've never had any problems
> with the existing setup, and I rarely get any inexplicable tripping of the
> circuit breakers. As far as I am aware, the old fuse boxes (even when fuses
> contained fuse wire) did what they were designed to do, with no problems.
>
> My fuse box has circuit-breakers for:
> Upstairs ring main
> Downstairs ring main
> Upstairs light circuit
> Downstairs lighting circuit
> Electric shower circuit
> External security lights circuit
>
> Obviously, I'd like to avoid the expense of updating it if I'm not under
> any legal obligation to change anything.

you're not

> Is there really a significant
> increase in electrical safety with the modern RCD units?

There are 20 something deaths from shock a year, mostly due to people doing idiotic things. RCDs reduce the risk. This is a long way down the list of Risky Things in Life, so is the oposite of a priority.

NT

John Rumm

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Jun 21, 2015, 11:51:01 PM6/21/15

to

On 21/06/2015 23:20, Jim x321x wrote:

> My house was built and wired in the 1980s and has an old-style fuse box.
> The old fuses have all been repeplaced with cirquit-breakers plugged into
> the fuse sockets. A couple of people, such as estate agents and
> electricians have raised eyebrows on seeing the box, telling me it should
> be changed for a modern RCD unit. Is this true? I've never had any problems

There is no legal requirement to change it.

> with the existing setup, and I rarely get any inexplicable tripping of the
> circuit breakers. As far as I am aware, the old fuse boxes (even when fuses
> contained fuse wire) did what they were designed to do, with no problems.

They did what they were supposed to - and will still do so. The main
thing your current setup lacks is RCD protection.

> My fuse box has circuit-breakers for:
> Upstairs ring main
> Downstairs ring main
> Upstairs light circuit
> Downstairs lighting circuit
> Electric shower circuit
> External security lights circuit
>
> Obviously, I'd like to avoid the expense of updating it if I'm not under
> any legal obligation to change anything. Is there really a significant
> increase in electrical safety with the modern RCD units?

RCDs represent a significant improvement in safety. Especially if you
ever use electrical tools / appliances outside. The lack of RCD
protection would also make adding or extending your existing
installation in a compliant way more difficult, should you need to do so.

(some will argue that the chances of being killed by an electric shock
in the home in the UK is vanishingly small, and indeed they are correct.
However that misses the significant number of non fatal injuries per
year (>200K hospital admissions), the vast majority of which would have
been prevented by a working RCD).

> What about if I rent the house to tenants? Will it then need to comply with
> the latest electrical regulation specs?

As long as its basically sound, then not necessarily. Many landlords
would take the view that replacing rewireable fuses is worth doing since
it removes the ability for tenants to abuse them, and possibly prevents
some call outs to the landlord / maintainer because they can't work out
how to replace a blown fuse.

--
Cheers,

John.

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

Message has been deleted

Andy Burns

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Jun 22, 2015, 3:22:55 AM6/22/15

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Chris Hogg wrote:

> Is it possible to get what I think are called RCBO's,
> (i.e. a combination of overload cut-out, MCB, with a residual current
> device, RCD), that plug into the slots currently occupied by the wire
> fuse holders

Plug-in MCBs are possible because they only require the same two
contacts (live in and out) that the old fuses used, but an RCBO requires
additional contacts (neutral in and out and an earth) so not feasible as
a plug-in replacement.

Andy Burns

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Jun 22, 2015, 3:27:58 AM6/22/15

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Andy Burns wrote:

> an RCBO requires additional contacts (neutral in and out and an
> earth)

Which makes me ask another question ...
Why does an RCBO require a functional earth, when an RCD doesn't?

spuorg...@gowanhill.com

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Jun 22, 2015, 3:33:28 AM6/22/15

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On Sunday, 21 June 2015 23:20:25 UTC+1, Jim x321x wrote:

> My house was built and wired in the 1980s and has an old-style fuse box.
> The old fuses have all been repeplaced with cirquit-breakers plugged into
> the fuse sockets.

There can be issues with doing this. Certain designs have gaps between the MCBs and the cover which would fail modern ingress protection rating against poking things in. Also the plug-in MCBs sometimes have a lower breaking capacity than 'conventional' MCBs.

For rental property electrics have to be 'safe' (and in Scotland from later this year, have an EICR - electrical condition report).

Given the age and current circuit arrangements it's likely that replacing the CU would be a fairly straightforward swap if the original wiring hasn't been buggered about with.

For renting you would also need mains powered interlinked smoke detectors.

Owain

phil...@gmail.com

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Jun 22, 2015, 3:44:34 AM6/22/15

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The earth connection enables the RCBO to trip even with a lost neutral connection.

Andy Burns

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Jun 22, 2015, 3:50:18 AM6/22/15

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phil...@gmail.com wrote:

> Andy Burns wrote:
>
>> Why does an RCBO require a functional earth, when an RCD doesn't?
>
> The earth connection enables the RCBO to trip even with a lost neutral connection.

I'm curious why have we ended-up with RCBOs that generally do have an FE
connection and RCDs that generally don't?

Brian-Gaff

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Jun 22, 2015, 4:06:46 AM6/22/15

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Well, I've never come across any rented property that has the very latest
fuse box/rcd. But that may just be coincidence. I do not go around checking
everyones houses I visit for rcds, only that a blind person can safely reach
the reset buttons!
In any case if you are using an outside applience, you use a plug in rcd
and then its as safe as anything can be.
Brian

--
From the Sofa of Brian Gaff Reply address is active
"John Rumm" <see.my.s...@nowhere.null> wrote in message
news:S8SdnWOCa5G-GxrI...@brightview.co.uk...

Robin

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Jun 22, 2015, 4:17:52 AM6/22/15

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spuorg...@gowanhill.com wrote:
> For renting you would also need mains powered interlinked smoke
> detectors.
>

In England? I'm not a landlord but several neighbours are and from their
chatter I thought even the new regs which apply from October only
required a smoke alarm on every floor - ie no need for mains powered or
interlinked in a bog standard non-HMO.

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

Jim x321x

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Jun 22, 2015, 4:56:09 AM6/22/15

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John Rumm <see.my.s...@nowhere.null> wrote in

news:S8SdnWOCa5G-GxrI...@brightview.co.uk:

>> with the existing setup, and I rarely get any inexplicable tripping
>> of the circuit breakers. As far as I am aware, the old fuse boxes
>> (even when fuses contained fuse wire) did what they were designed to
>> do, with no problems.
>
> They did what they were supposed to - and will still do so. The main
> thing your current setup lacks is RCD protection.

Thanks to all for the excellently helpful advice.

If I added an RCD covering the entire house (without replacing the existing
fuse box which is already fitted with MCBs, would that constitute a change
to the wiring and thus require building control notification?

Would doing this significantly improve the house's safety rating in the
eyes of, say, a house-purchaser's surveyor?

I note that in another thread recently, someone seemed alarmed that someone
was planning to install an electric shower without RCD protection. That's
partly what got me thinking about this issue.

Jim

Jim x321x

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Jun 22, 2015, 5:05:05 AM6/22/15

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spuorg...@gowanhill.com wrote in
news:6615a8b5-00ed-486b...@googlegroups.com:

>> My house was built and wired in the 1980s and has an old-style fuse
>> box.
>
>> The old fuses have all been repeplaced with cirquit-breakers plugged
>> into
>
>> the fuse sockets.
>
> There can be issues with doing this. Certain designs have gaps between
> the MCBs and the cover which would fail modern ingress protection
> rating against poking things in. Also the plug-in MCBs sometimes have
> a lower breaking capacity than 'conventional' MCBs.

Thanks. I have to admit, that there *is*, arguably an issue with the
plastic cover that originally covered all the fuses. The subsequently-
installed MCBs stick out to far to allow the old cover to be attached. So I
simply left it off. My thinking was that MCBs should probably be in plain
view anyway, because one should be able to access them quickly. Also,
unenlightened tenenats and/or their guests might not know where the MCbs
are located if they were all covered with an opaque plastic cover that's
screwed on.

I suppose I could quite easily modify the cover to make it deep enough to
cover the MCBs without obstructing free flip-switch operation.

BTW, I am in England, so not bound by regional Scottish regulations.

Jim

Jim x321x

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Jun 22, 2015, 5:13:38 AM6/22/15

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John Rumm <see.my.s...@nowhere.null> wrote in news:S8SdnWOCa5G-

GxrInZ2dnU...@brightview.co.uk:

> (some will argue that the chances of being killed by an electric shock
> in the home in the UK is vanishingly small, and indeed they are correct.
> However that misses the significant number of non fatal injuries per
> year (>200K hospital admissions), the vast majority of which would have
> been prevented by a working RCD).

Thanks for the input. You confirm what I thought. In fact, it seems likely
to me that more accidents are likely to be caused by a house's power being
unexpectedly cut off due to a RCD misdiagnosing a fault - especially at
night. Elderly an infirm people suddenly finding themselves walking around
in pitch darkness, having to fumble their way to the CU. Surely that would
be a dangersous situation for some, no? It would be interesting to know the
statistics regarding how many people have suffered injury that way, vs. how
many have suffered injury due to a fuse failing to blow, or a MCB failing
to trip.

Jim

Message has been deleted

Andy Burns

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Jun 22, 2015, 5:23:03 AM6/22/15

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Jim x321x wrote:

> it seems likely to me that more accidents are likely to be caused by
> a house's power being unexpectedly cut off due to a RCD misdiagnosing
> a fault - especially at night. Elderly an infirm people suddenly
> finding themselves walking around in pitch darkness, having to fumble
> their way to the CU.

Hence newer installations having at least two RCDs with circuits split
between them, or RCBOs per circuit, so that faults on one circuit affect
fewer (or no) other circuits ... rather than being in pitch darkness you
could get a bit of light from upstairs reaching downstairs, or use
floor/table lights instead of ceiling lights etc.

John Rumm

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Jun 22, 2015, 5:54:00 AM6/22/15

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On 22/06/2015 09:06, Brian-Gaff wrote:
> Well, I've never come across any rented property that has the very latest
> fuse box/rcd. But that may just be coincidence. I do not go around checking
> everyones houses I visit for rcds, only that a blind person can safely reach
> the reset buttons!

Indeed - how would you cope with re-wireing a BS3036 style fuse?

> In any case if you are using an outside applience, you use a plug in rcd
> and then its as safe as anything can be.

Yup that will help.

John Rumm

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Jun 22, 2015, 6:05:10 AM6/22/15

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On 22/06/2015 09:56, Jim x321x wrote:
> John Rumm <see.my.s...@nowhere.null> wrote in
> news:S8SdnWOCa5G-GxrI...@brightview.co.uk:
>
>>> with the existing setup, and I rarely get any inexplicable tripping
>>> of the circuit breakers. As far as I am aware, the old fuse boxes
>>> (even when fuses contained fuse wire) did what they were designed to
>>> do, with no problems.
>>
>> They did what they were supposed to - and will still do so. The main
>> thing your current setup lacks is RCD protection.
>
>
> Thanks to all for the excellently helpful advice.
>
> If I added an RCD covering the entire house (without replacing the existing
> fuse box which is already fitted with MCBs, would that constitute a change
> to the wiring and thus require building control notification?

Firstly you don't want a single RCD covering the whole house - that is a
practice that was common during the 15th edition, but is deprecated now
since it offers no "discrimination" in the event of a fault (i.e. the
fault will take out the supply to the whole house, not just the circuit
causing the problem). So many circuits on one RCD are also more prone to
nuisance tripping in the first place.

Changing a CU is "notifiable", although if done right no one is going to
whinge if you don't.

> Would doing this significantly improve the house's safety rating in the
> eyes of, say, a house-purchaser's surveyor?

Only if the purchaser is sufficiently clued up. You may find an older CU
etc would be commented on during a survey, but only in as much as the
surveyor might comment that you could get an electrical report if
concerned.

So if your only reason for the change is to make the house more
saleable, I would not bother. If however you are planning to carry on
living there, then its worth it (IMHO) for other reasons.

> I note that in another thread recently, someone seemed alarmed that someone
> was planning to install an electric shower without RCD protection. That's
> partly what got me thinking about this issue.

Its possible to install a shower safely without one - and prior to the
17th edition it was possible (and not uncommon) to do so. Having said
that, its very sensible to include a RCD for a shower, and now the 17th
edition mandates it.

For your installation with relatively few circuits, the "nicest"
solution would be an "all RCBO" installation. That is one where you use
RCBOs (Residual Current Circuit breaker with Overload protection) - i.e.
a combined MCB and RCD in one. That way you get the best of both worlds
RCD protection on every circuit, but also perfect discrimination - a RCD
trip will only deactivate the circuit with the fault and leave the rest
untouched.

John Rumm

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Jun 22, 2015, 6:15:04 AM6/22/15

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On 22/06/2015 10:13, Jim x321x wrote:
> John Rumm <see.my.s...@nowhere.null> wrote in news:S8SdnWOCa5G-
> GxrInZ2dnU...@brightview.co.uk:
>
>> (some will argue that the chances of being killed by an electric shock
>> in the home in the UK is vanishingly small, and indeed they are correct.
>> However that misses the significant number of non fatal injuries per
>> year (>200K hospital admissions), the vast majority of which would have
>> been prevented by a working RCD).
>
> Thanks for the input. You confirm what I thought. In fact, it seems likely
> to me that more accidents are likely to be caused by a house's power being
> unexpectedly cut off due to a RCD misdiagnosing a fault - especially at
> night. Elderly an infirm people suddenly finding themselves walking around
> in pitch darkness, having to fumble their way to the CU. Surely that would
> be a dangersous situation for some, no?

This is why the "whole house" RCD setup is now no longer permitted.
Trips and falls in the house are more likely to injure people than
electric shocks in the first place.

> It would be interesting to know the
> statistics regarding how many people have suffered injury that way, vs. how
> many have suffered injury due to a fuse failing to blow, or a MCB failing
> to trip.

RCDs (in this scenario) are primarily about shock protection from what
used to be called "direct contact" (now "basic protection") - i.e. you
come into contact with something that is supposed to be live, but you
are not normally supposed to be able to touch it (e.g. a cut flex on the
mower). MCBs and Fuses offer almost *no* direct contact protection since
the current that flows through you is insufficient to trip a MCB or blow
a fuse - but still plenty to injure or kill you.

Fuses and MCBs only offer shock protection in "indirect contact" or
"fault protection" scenarios - i.e. preventing shocks from coming into
contact with metalwork that should *not* be live normally, but has
become so as a result of a fault. (since said metal work should be
earthed, that creates a path for a large fault current to flow, which in
turn with de-energise the circuit due to operation of the MCB/fuse.

John Rumm

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Jun 22, 2015, 6:16:56 AM6/22/15

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On 22/06/2015 08:15, Chris Hogg wrote:
> Not answering your question, but adding one of my own as I have a
> similar situation in my mother's house. She has an old fuse box with
> wired fuses. Is it possible to get what I think are called RCBO's,

> (i.e. a combination of overload cut-out, MCB, with a residual current
> device, RCD), that plug into the slots currently occupied by the wire

> fuse holders, or does that require a whole new consumer unit?

You can get plug in MCBs for old Wylex style boxes, but not plug in
RCBOs, since a RCBO needs the neutral to pass through it as well as the
live, and there is no access to that from the socket on the fusebox.

Mike Clarke

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Jun 22, 2015, 6:18:05 AM6/22/15

to

On 22/06/2015 11:05, John Rumm wrote:
> For your installation with relatively few circuits, the "nicest"
> solution would be an "all RCBO" installation. That is one where you use
> RCBOs (Residual Current Circuit breaker with Overload protection) - i.e.
> a combined MCB and RCD in one. That way you get the best of both worlds
> RCD protection on every circuit, but also perfect discrimination - a RCD
> trip will only deactivate the circuit with the fault and leave the rest
> untouched.

The OP mentioned separate upstairs and downstairs light circuits. It's
possible that the landing light might have "borrowed" the neutral from
downstairs. If so this would need to be rectified before RCBO's could be
used for these two circuits.

--
Mike Clarke

John Rumm

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Jun 22, 2015, 6:18:41 AM6/22/15

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They don't necessarily, although some do have one.

The additional earth connection allows the RCD section to trip on
additional fault scenarios that would not otherwise be detected.

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Jun 22, 2015, 6:37:30 AM6/22/15

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On Monday, 22 June 2015 11:05:10 UTC+1, John Rumm wrote:
> On 22/06/2015 09:56, Jim x321x wrote:
> > John Rumm <see.my.s...@nowhere.null> wrote in
> > news:S8SdnWOCa5G-GxrI...@brightview.co.uk:
> >
> >>> with the existing setup, and I rarely get any inexplicable tripping
> >>> of the circuit breakers. As far as I am aware, the old fuse boxes
> >>> (even when fuses contained fuse wire) did what they were designed to
> >>> do, with no problems.
> >>
> >> They did what they were supposed to - and will still do so. The main
> >> thing your current setup lacks is RCD protection.
> >
> >
> > Thanks to all for the excellently helpful advice.
> >
> > If I added an RCD covering the entire house (without replacing the existing
> > fuse box which is already fitted with MCBs, would that constitute a change
> > to the wiring and thus require building control notification?
>
> Firstly you don't want a single RCD covering the whole house - that is a
> practice that was common during the 15th edition, but is deprecated now
> since it offers no "discrimination" in the event of a fault (i.e. the
> fault will take out the supply to the whole house, not just the circuit
> causing the problem). So many circuits on one RCD are also more prone to
> nuisance tripping in the first place.

A single RCD is moderately likely to not even work.

> > Would doing this significantly improve the house's safety rating in the
> > eyes of, say, a house-purchaser's surveyor?
>
> Only if the purchaser is sufficiently clued up. You may find an older CU
> etc would be commented on during a survey, but only in as much as the
> surveyor might comment that you could get an electrical report if
> concerned.

Surveys say get it checked regardless. A buyer that understands RCDs - few do - is one that can do the job themselves if they want.

> So if your only reason for the change is to make the house more
> saleable, I would not bother. If however you are planning to carry on
> living there, then its worth it (IMHO) for other reasons.

Work out the cost & size of risk reduction. Compare with other options. The benefit per pound is far from top of the list.

NT

GB

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Jun 22, 2015, 6:39:15 AM6/22/15

to

On 22/06/2015 04:51, John Rumm wrote:

> (some will argue that the chances of being killed by an electric shock
> in the home in the UK is vanishingly small,

About the same as the chance of winning the lottery (give or take a
factor of 10), yet many people buy lottery tickets.

GB

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Jun 22, 2015, 6:42:34 AM6/22/15

to

On 22/06/2015 11:05, John Rumm wrote:

> So if your only reason for the change is to make the house more
> saleable, I would not bother.

If you simply want to make it more saleable, you could perhaps put a
dummy new-style fuse box in a prominent position, and lock the cupboard
with the real one in. :)

Graham.

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Jun 22, 2015, 7:52:38 AM6/22/15

to

On Mon, 22 Jun 2015 10:54:02 +0100, John Rumm
<see.my.s...@nowhere.null> wrote:

>On 22/06/2015 09:06, Brian-Gaff wrote:
>> Well, I've never come across any rented property that has the very latest
>> fuse box/rcd. But that may just be coincidence. I do not go around checking
>> everyones houses I visit for rcds, only that a blind person can safely reach
>> the reset buttons!
>
>Indeed - how would you cope with re-wireing a BS3036 style fuse?

I bet Brian could do that with no problem.
I bet you and I could do it blindfolded it we tried, I never have!

I've re spooled plenty of 35mm cassettes using a changing bag, and
loaded various film sizes into the spiral if a developing tank in
complete darkness.

I'm not suggesting for a moment that a sighted person in the dark
equates to a blind person. That would indeed be arrogant.

--

Graham.

%Profound_observation%

John Rumm

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Jun 22, 2015, 10:36:57 AM6/22/15

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On 22/06/2015 12:52, Graham. wrote:
> On Mon, 22 Jun 2015 10:54:02 +0100, John Rumm
> <see.my.s...@nowhere.null> wrote:
>
>> On 22/06/2015 09:06, Brian-Gaff wrote:
>>> Well, I've never come across any rented property that has the very latest
>>> fuse box/rcd. But that may just be coincidence. I do not go around checking
>>> everyones houses I visit for rcds, only that a blind person can safely reach
>>> the reset buttons!
>>
>> Indeed - how would you cope with re-wireing a BS3036 style fuse?
>
> I bet Brian could do that with no problem.
> I bet you and I could do it blindfolded it we tried, I never have!

More than likely - but familiarity is the key (and knowing what you are
trying to achieve)

For an unskilled user attempting to identify the failed fuse, locate the
right rating of spare fuse wire, effecting the replacement and then
getting the fuse back into the CU - all in the dark, when you have never
even bother looking at the fuse box in the past, is quite a "big ask"!
Especially when compared to finding which MCB has tripped and flipping
the switch.

unread,

Jun 22, 2015, 11:30:36 AM6/22/15

to

I don't see that as a failure rate, just additional work to be done to
rectify the earth leakage faults that may have unknowingly have been
present for decades.

Not that I'm saying a whole house RCD was ever the ideal solution.

--

Graham.

%Profound_observation%

Graham.

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Jun 22, 2015, 11:33:50 AM6/22/15

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...Nothing another ZAP won't cure (allegedly).

--

Graham.

%Profound_observation%

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Jun 22, 2015, 1:39:23 PM6/22/15

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In article <qLWdnaCZZd4bgBXI...@brightview.co.uk>,

In our previous house, which used wired fuses, I always had ready wired
spare fuses to hand.

Charles Hope

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Jun 22, 2015, 1:39:23 PM6/22/15

to

In article <qLWdnaOZZd5CgBXI...@brightview.co.uk>,

John Rumm <see.my.s...@nowhere.null> wrote:
> On 22/06/2015 11:18, Mike Clarke wrote:
> > On 22/06/2015 11:05, John Rumm wrote:
> >> For your installation with relatively few circuits, the "nicest"
> >> solution would be an "all RCBO" installation. That is one where you use
> >> RCBOs (Residual Current Circuit breaker with Overload protection) - i.e.
> >> a combined MCB and RCD in one. That way you get the best of both worlds
> >> RCD protection on every circuit, but also perfect discrimination - a RCD
> >> trip will only deactivate the circuit with the fault and leave the rest
> >> untouched.
> >
> > The OP mentioned separate upstairs and downstairs light circuits. It's
> > possible that the landing light might have "borrowed" the neutral from
> > downstairs. If so this would need to be rectified before RCBO's could be
> > used for these two circuits.

> Indeed - there are a few potential problems to crawl out of the
> woodwork. Probably worth anyone thinking o doing their own CU swap,
> having a read through of:

> http://wiki.diyfaq.org.uk/index.php?title=Changing_a_consumer_unit

I did mine in the late 70s - shortly after we moved in here. The
Electricity Board man came at 8am - first call - to isolate. I suggested
that if he came back at 10am to reconnect, I'd be able to put the kettle on
when he'd finished. He arrived at 10- on the dot - and we had the kettle
going shortly afterwards.

Charles Hope

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Jun 22, 2015, 1:39:23 PM6/22/15

to

In article <d3c27fe8-b0c0-4ae8...@googlegroups.com>,

<tabb...@gmail.com> wrote:
> On Monday, 22 June 2015 11:05:10 UTC+1, John Rumm wrote:
> > On 22/06/2015 09:56, Jim x321x wrote:
> > > John Rumm <see.my.s...@nowhere.null> wrote in
> > > news:S8SdnWOCa5G-GxrI...@brightview.co.uk:
> > >
> > >>> with the existing setup, and I rarely get any inexplicable tripping
> > >>> of the circuit breakers. As far as I am aware, the old fuse boxes
> > >>> (even when fuses contained fuse wire) did what they were designed
> > >>> to do, with no problems.
> > >>
> > >> They did what they were supposed to - and will still do so. The main
> > >> thing your current setup lacks is RCD protection.
> > >
> > >
> > > Thanks to all for the excellently helpful advice.
> > >
> > > If I added an RCD covering the entire house (without replacing the
> > > existing fuse box which is already fitted with MCBs, would that
> > > constitute a change to the wiring and thus require building control
> > > notification?
> >
> > Firstly you don't want a single RCD covering the whole house - that is
> > a practice that was common during the 15th edition, but is deprecated
> > now since it offers no "discrimination" in the event of a fault (i.e.
> > the fault will take out the supply to the whole house, not just the
> > circuit causing the problem). So many circuits on one RCD are also
> > more prone to nuisance tripping in the first place.

> A single RCD is moderately likely to not even work.

mine has - more than once. But if a single one doesn't work, why should
more than one?

Charles Hope

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Jun 22, 2015, 1:39:24 PM6/22/15

to

In article <ob8goalbvo9ptee6d...@4ax.com>, Graham.

If you modify the cover corectly, you are left with a retaining frame which
holds the MCBs in place/

GB

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Jun 22, 2015, 1:54:49 PM6/22/15

to

As all marriages end either in divorce or death, it's amazing that
divorce is not more popular, really.

tabb...@gmail.com

unread,

Jun 22, 2015, 2:28:35 PM6/22/15

to

On Monday, 22 June 2015 15:47:38 UTC+1, John Rumm wrote:

What I meant is in some cases you will have no power because the install trips the RCD when powered

> >>> Would doing this significantly improve the house's safety rating
> >>> in the eyes of, say, a house-purchaser's surveyor?
> >>
> >> Only if the purchaser is sufficiently clued up. You may find an
> >> older CU etc would be commented on during a survey, but only in as
> >> much as the surveyor might comment that you could get an
> >> electrical report if concerned.
> >
> > Surveys say get it checked regardless. A buyer that understands RCDs
> > - few do - is one that can do the job themselves if they want.
>
> Indeed. Hence my comment about it not being something that will help
> "sell" a house.
>
> >> So if your only reason for the change is to make the house more
> >> saleable, I would not bother. If however you are planning to carry
> >> on living there, then its worth it (IMHO) for other reasons.
> >
> > Work out the cost & size of risk reduction. Compare with other
> > options. The benefit per pound is far from top of the list.
>
> If your only criterion is avoidance of death due to electrocution, then
> the argument is plausible, since from a statistical point of view you
> may as well ignore the risk of death - its low enough to be insignificant.

Death risks all come with injury risks too. Its harder to get injury risks, but if you tabulate them its still not a priority on the table of preventable risks.

> None of that however diminishes the effectiveness of a RCD at preventing
> shock injury - the occurrences of which are commonplace rather than
> rare. (100's K of hospital admissions per year)

How do you conclude that all those are injuries? Last time they wanted to admit me all I needed was tea & aspirin.

NT

ARW

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Jun 22, 2015, 2:31:16 PM6/22/15

to

"GB" <NOTso...@microsoft.com> wrote in message
news:mm9i2m$7s9$1...@dont-email.me...

It's a close run race. And there all those thousands of separated but not
divorces couples.

--
Adam

ARW

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Jun 22, 2015, 2:44:39 PM6/22/15

to

"Andy Burns" <usenet....@adslpipe.co.uk> wrote in message
news:l6udnZg2KpilIxrI...@brightview.co.uk...
> phil...@gmail.com wrote:

>
>> Andy Burns wrote:
>>
>>> Why does an RCBO require a functional earth, when an RCD doesn't?
>>
>> The earth connection enables the RCBO to trip even with a lost neutral
>> connection.
>

> I'm curious why have we ended-up with RCBOs that generally do have an FE
> connection and RCDs that generally don't?

Cost?

http://www.eaton.com/Eaton/OurCompany/NewsEvents/NewsReleases/PCT_255273

But then Eatons RCBO do have an earth lead.
--
Adam

Andy Burns

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Jun 22, 2015, 2:47:03 PM6/22/15

to

Charles Hope wrote:

> when I redecorate out stairwell - which is quite an epic, in going put in
> an LED fitting in the ceiling; 2Ds only last about 4 years. And - I'm going
> to get one with an emergency battery pack.

The batteries only last about 4 years, if you're trying to avoid having
to access it again, might be worth modifying the wiring so the battery
is e.g. in the loft for easy access ...

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Jun 22, 2015, 3:18:18 PM6/22/15

to

<tabb...@gmail.com> wrote in message
news:4b2d4d38-8d10-4442...@googlegroups.com...

> Someone going to hospital because they got scared doesn't mean they're
> injured.

They would be better off going to the launderette.

--
Adam

ARW

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Jun 22, 2015, 3:40:40 PM6/22/15

to

<tabb...@gmail.com> wrote in message
news:a13ad498-9d25-47d8...@googlegroups.com...

> On Sunday, 21 June 2015 23:20:25 UTC+1, Jim x321x wrote:
>> My house was built and wired in the 1980s and has an old-style fuse box.

>

>> Is there really a significant
>> increase in electrical safety with the modern RCD units?
>

> There are 20 something deaths from shock a year, mostly due to people
> doing idiotic things. RCDs reduce the risk. This is a long way down the
> list of Risky Things in Life, so is the oposite of a priority.

So what what would you prioritize?

Smoke alarms would be my number 1 - even if they are just battery powered
ones.

Number 2 would be to have an escape plan if there was a fire and the smokes
sounded.

And number 3 for safety in the home IMHO is RCD protection at the CU (at
least for the socket circuits).

--
Adam

ARW

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Jun 22, 2015, 4:20:17 PM6/22/15

to

"Graham." <m...@privicy.net> wrote in message
news:vv9goadfoadl89cfs...@4ax.com...

>
> I don't see that as a failure rate, just additional work to be done to
> rectify the earth leakage faults that may have unknowingly have been
> present for decades.

What is wrong with rectifying a fault?

--
Adam

tabb...@gmail.com

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Jun 22, 2015, 4:31:38 PM6/22/15

to

On Monday, 22 June 2015 20:40:40 UTC+1, ARW wrote:
> nt wrote in message

> news:a13ad498-9d25-47d8...@googlegroups.com...
> > On Sunday, 21 June 2015 23:20:25 UTC+1, Jim x321x wrote:
> >> My house was built and wired in the 1980s and has an old-style fuse box.
>
> >
> >> Is there really a significant
> >> increase in electrical safety with the modern RCD units?
> >
> > There are 20 something deaths from shock a year, mostly due to people
> > doing idiotic things. RCDs reduce the risk. This is a long way down the
> > list of Risky Things in Life, so is the oposite of a priority.
>
>
> So what what would you prioritize?

Look at the top 10 killers.
http://www.cdc.gov/nchs/fastats/leading-causes-of-death.htm

The top 2 are heart disease & cancer. They kill half the population. Expert concensus is half these deaths are readily avoidable by healthier eating, not smoking & some exercise. These are the number 1 priorities.

The rest of the list is different here versus US. Traffic accidents, septicaemia & medical errors featuer highly here, all of which are fairly straightforward to reduce.

Accidents: diy causes no lack of those, so getting informed re power tool risks etc.

Diabetes risk can be reduced by avoiding high sugar diet.

> Smoke alarms would be my number 1 - even if they are just battery powered
> ones.

There were 1000 deaths a year in house fires before they became the norm, now its about 200.

> Number 2 would be to have an escape plan if there was a fire and the smokes
> sounded.
>
> And number 3 for safety in the home IMHO is RCD protection at the CU (at
> least for the socket circuits).

20 odd deaths a year there.

I think we suffer warning fatigue. 'Yes I know I've heard it 1000 times but don't know how to' sort of thing. Its good to look at diy specific risks but I think its good to slot them into the big picture.

NT

ARW

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Jun 22, 2015, 4:51:09 PM6/22/15

to

<tabb...@gmail.com> wrote in message
news:2d24e921-6cb4-4a9a...@googlegroups.com...

> On Monday, 22 June 2015 20:40:40 UTC+1, ARW wrote:
>> nt wrote in message
>> news:a13ad498-9d25-47d8...@googlegroups.com...
>> > On Sunday, 21 June 2015 23:20:25 UTC+1, Jim x321x wrote:
>> >> My house was built and wired in the 1980s and has an old-style fuse
>> >> box.
>>
>> >
>> >> Is there really a significant
>> >> increase in electrical safety with the modern RCD units?
>> >
>> > There are 20 something deaths from shock a year, mostly due to people
>> > doing idiotic things. RCDs reduce the risk. This is a long way down the
>> > list of Risky Things in Life, so is the oposite of a priority.
>>
>>
>> So what what would you prioritize?
>
> Look at the top 10 killers.
> http://www.cdc.gov/nchs/fastats/leading-causes-of-death.htm
>
> The top 2 are heart disease & cancer. They kill half the population.
> Expert concensus is half these deaths are readily avoidable by healthier
> eating, not smoking & some exercise. These are the number 1 priorities.

A lifesyle choice is not relevant to diy or general risks in the house.

--
Adam

Robin

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Jun 22, 2015, 5:14:25 PM6/22/15

to

ARW wrote:
> "Robin" <rb...@hotmail.com> wrote in message
> news:mm8g8u$9fi$1...@dont-email.me...
>> spuorg...@gowanhill.com wrote:
>>> For renting you would also need mains powered interlinked smoke
>>> detectors.
>>>
>>
>> In England? I'm not a landlord but several neighbours are and from
>> their chatter I thought even the new regs which apply from October
>> only required a smoke alarm on every floor - ie no need for mains
>> powered or interlinked in a bog standard non-HMO.
>
> What new regs?

draft at present:
http://www.legislation.gov.uk/ukdsi/2015/9780111133439/contents

summary from draft ex.memo:

"2.1 These Regulations require landlords in the private rented sector in
England to ensure that a smoke alarm is equipped on every storey of
their rented dwelling when occupied under a tenancy, and that a carbon
monoxide alarm is equipped in any room which contains a solid fuel
burning combustion appliance. They also require landlords to ensure that
such alarms are in proper working order at the start of a new tenancy.
In addition, the Regulations amend the conditions which must be included
in a licence under Part 2 or 3 of the Housing Act 2004 ("the 2004 Act")
in respect of smoke and carbon monoxide alarms."

Landlords responsible for testing alarms at start of each tenancy but
AIUI *not* periodically thereafter.

> BTW I have been suggesting for years that landlords and home owners
> whilst I am there for other work and making a mess of a wall whilst
> installing a cable for some other job should fork out a litle bit
> extra for a mains powered interlinked smoke alarm install.

No quarrel from me. I installed a possibly absurd 7 smoke/heat in this
3-bed terrace (including one in the loft) on the basis the earlier the
warning of fire behind a closed door the better the chance of getting
out. Just not what the draft regs require for run-of-the-mill lets.

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

spuorg...@gowanhill.com

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Jun 22, 2015, 5:32:50 PM6/22/15

to

On Monday, 22 June 2015 18:54:49 UTC+1, GB wrote:
> As all marriages end either in divorce or death, it's amazing that
> divorce is not more popular, really.

But both people get divorced; most of the time only one partner gets widow(er)ed.

So you have a 50% chance of getting less than half the money with divorce vs a 50% chance of getting all the money if you live or not caring if you die.

Should I sell my RCDs on ebay and buy lottery tickets with the money?

Owain

John Rumm

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Jun 22, 2015, 5:53:32 PM6/22/15

to

That's hardly an ongoing problem... it means you have either a fault, or
too much combined leakage. Both fixable, neither relevant since no one
will be fitting a single whole house RCD anyway.

>>>> So if your only reason for the change is to make the house
>>>> more saleable, I would not bother. If however you are planning
>>>> to carry on living there, then its worth it (IMHO) for other
>>>> reasons.
>>>
>>> Work out the cost & size of risk reduction. Compare with other
>>> options. The benefit per pound is far from top of the list.
>>
>> If your only criterion is avoidance of death due to electrocution,
>> then the argument is plausible, since from a statistical point of
>> view you may as well ignore the risk of death - its low enough to
>> be insignificant.
>
> Death risks all come with injury risks too. Its harder to get injury
> risks, but if you tabulate them its still not a priority on the table
> of preventable risks.

That is nonsense, as you are well aware.

>> None of that however diminishes the effectiveness of a RCD at
>> preventing shock injury - the occurrences of which are commonplace
>> rather than rare. (100's K of hospital admissions per year)
>
> How do you conclude that all those are injuries?

These are the cases where either an ambulance was called or someone went
/ was taken to A&E.

They will include the full range of injuries from a mild burn - no real
treatment required, to life changing and permanent injury / disfigurement.

I have posted links to the stats before. Even if we are only talking
about 20K serious injuries, that is ample justification for spending a
couple of hundred quid on your home for your family's protection in my
view.

If we apply your logic, there are only 10s of K serious car accident
injuries a year, so why waste money on seatbelts or MoT tests?

> Last time they
> wanted to admit me all I needed was tea & aspirin.

spuorg...@gowanhill.com

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Jun 23, 2015, 5:37:02 AM6/23/15

to

On Monday, 22 June 2015 22:53:32 UTC+1, John Rumm wrote:
> > What I meant is in some cases you will have no power because the
> > install trips the RCD when powered
> That's hardly an ongoing problem... it means you have either a fault, or
> too much combined leakage. Both fixable, neither relevant since no one
> will be fitting a single whole house RCD anyway.

And of course we do some basic tests before we reconnect circuits (or even better, before we disconnect the old board) don't we...?

> I have posted links to the stats before. Even if we are only talking
> about 20K serious injuries, that is ample justification for spending a
> couple of hundred quid on your home for your family's protection in my
> view.

Having cut through a live cable protected by 30A fuse wire (which didn't blow) and seen the resulting fireworks (and hole in my cutters) I'm quite happy to have MCBs and RCDs. A new dual-RCD consumer unit is only about £50 now.

Owain

Robin

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Jun 23, 2015, 5:49:15 AM6/23/15

to

And what would you estimate as the cost of fitting it plus putting right
whatever the installer decides needs to be done before re-energising? I
ask as it's unlikely the OP would have asked the questions he did if he
were competent to DIY a change of CU.

Jim x321x

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Jun 23, 2015, 6:05:28 AM6/23/15

to

"ARW" <adamwa...@blueyonder.co.uk> wrote in news:mm9lev$mlf$1@dont-
email.me:

>> do that myself. (Cut the face off the cover, and then fix the remaining
>> part where it was intended to be.)
>
>
> The cover probably has knockouts on it to do that.
>
> --
> Adam
>

I just looked. It DOES!! (I could KISS you! :) I cut along the groove with
a stanley knife and hey-presto, I now have the cover back on, minus the
face. Now it all looks so much more respectable!

It's as if Wylex anticipated the coming of the MCB!

Jim

John Rumm

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Jun 23, 2015, 7:34:00 AM6/23/15

to

I guess that depends on the size of the CU and the location in the
country. I would have thought £150 - £200 would be the minimum including
parts.

John Rumm

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Jun 23, 2015, 7:35:05 AM6/23/15

to

My emergency lights have been in seven or eight years so far - still on
the same batteries.

tabb...@gmail.com

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Jun 23, 2015, 8:07:23 AM6/23/15

to

On Monday, 22 June 2015 21:51:09 UTC+1, ARW wrote:
> nt wrote in message
> news:2d24e921-6cb4-4a9a...@googlegroups.com...
> > On Monday, 22 June 2015 20:40:40 UTC+1, ARW wrote:
> >> nt wrote in message
> >> news:a13ad498-9d25-47d8...@googlegroups.com...
> >> > On Sunday, 21 June 2015 23:20:25 UTC+1, Jim x321x wrote:
> >> >> My house was built and wired in the 1980s and has an old-style fuse
> >> >> box.
> >>
> >> >
> >> >> Is there really a significant
> >> >> increase in electrical safety with the modern RCD units?
> >> >
> >> > There are 20 something deaths from shock a year, mostly due to people
> >> > doing idiotic things. RCDs reduce the risk. This is a long way down the
> >> > list of Risky Things in Life, so is the oposite of a priority.
> >>
> >>
> >> So what what would you prioritize?
> >
> > Look at the top 10 killers.
> > http://www.cdc.gov/nchs/fastats/leading-causes-of-death.htm
> >
> > The top 2 are heart disease & cancer. They kill half the population.
> > Expert concensus is half these deaths are readily avoidable by healthier
> > eating, not smoking & some exercise. These are the number 1 priorities.
>
> A lifesyle choice is not relevant to diy or general risks in the house.

Risks and the cost of avoiding them are 100% relevant to risks and the cost of avoiding them

tabb...@gmail.com

unread,

Jun 23, 2015, 8:12:46 AM6/23/15

to

On Monday, 22 June 2015 22:53:32 UTC+1, John Rumm wrote:

> On 22/06/2015 19:28, nt wrote:
> > On Monday, 22 June 2015 15:47:38 UTC+1, John Rumm wrote:
> >> On 22/06/2015 11:37, nt wrote:
> >>> On Monday, 22 June 2015 11:05:10 UTC+1, John Rumm wrote:
> >>>> On 22/06/2015 09:56, Jim x321x wrote:
> >>>>> John Rumm <see.my.s...@nowhere.null> wrote in
> >>>>> news:S8SdnWOCa5G-GxrI...@brightview.co.uk:

> >>> A single RCD is moderately likely to not even work.
> >>
> >> True, but the failure rate is not high enough to make that relevant
> >> I would say. (IIRC, 15% of those that have never been tested may
> >> fail to operate when they should - but that sill leaves 75% that
> >> will work and potentially prevent an injury)
> >
> > What I meant is in some cases you will have no power because the
> > install trips the RCD when powered
>
> That's hardly an ongoing problem...

its an issue with the op's plan. For an op with limited understanding it is also liable to be an ongoing problem, fwiw

> it means you have either a fault, or
> too much combined leakage. Both fixable,

by the op? I dont assume so

> neither relevant since no one
> will be fitting a single whole house RCD anyway.

aiui the op was considering it

> >>>> So if your only reason for the change is to make the house
> >>>> more saleable, I would not bother. If however you are planning
> >>>> to carry on living there, then its worth it (IMHO) for other
> >>>> reasons.
> >>>
> >>> Work out the cost & size of risk reduction. Compare with other
> >>> options. The benefit per pound is far from top of the list.
> >>
> >> If your only criterion is avoidance of death due to electrocution,
> >> then the argument is plausible, since from a statistical point of
> >> view you may as well ignore the risk of death - its low enough to
> >> be insignificant.
> >
> > Death risks all come with injury risks too. Its harder to get injury
> > risks, but if you tabulate them its still not a priority on the table
> > of preventable risks.
>
> That is nonsense, as you are well aware.

really? do tell

> >> None of that however diminishes the effectiveness of a RCD at
> >> preventing shock injury - the occurrences of which are commonplace
> >> rather than rare. (100's K of hospital admissions per year)
> >
> > How do you conclude that all those are injuries?
>
> These are the cases where either an ambulance was called or someone went
> / was taken to A&E.
>
> They will include the full range of injuries from a mild burn - no real
> treatment required, to life changing and permanent injury / disfigurement.

so obviously not the number of injuries. Maybe you're not familiar with how the nhs works on this point.

> I have posted links to the stats before. Even if we are only talking
> about 20K serious injuries, that is ample justification for spending a
> couple of hundred quid on your home for your family's protection in my
> view.
>
> If we apply your logic, there are only 10s of K serious car accident
> injuries a year, so why waste money on seatbelts or MoT tests?

that has nothing to do with what I said

> > Last time they
> > wanted to admit me all I needed was tea & aspirin.

NT

GB

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Jun 23, 2015, 9:43:21 AM6/23/15

to

On 22/06/2015 22:32, spuorg...@gowanhill.com wrote:

> Should I sell my RCDs on ebay and buy lottery tickets with the money?

What a splendid question!

Assuming that you don't replace the RCDs:

About 1 in 1000 : You'll win some amount, probably modest, and never be
electrocuted. You'll be a winner overall.

About 999 in 1000: You'll win nothing, and never be electrocuted. You'll
neither win nor lose.

About 1 in 1,000,000 : You'll be electrocuted, in which case what you
have won won't matter, and for some brief period of agony you'll regret
your decision.

John Rumm

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Jun 23, 2015, 12:14:52 PM6/23/15

to

On 23/06/2015 10:50, Robin wrote:

Probably depends on the area of the country... I would have thought a
straight swap would start at £200 - £300.

John Rumm

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Jun 23, 2015, 12:20:21 PM6/23/15

to

Not only that, as had been pointed out at various times, one insures
against losses that one can't otherwise replace. I would include wife
and children in that category, so a one off premium of a couple of
hundred for smoke alarms and RCDs sounds like a very worthwhile investment.

John Rumm

unread,

Jun 23, 2015, 12:22:36 PM6/23/15

to

Let see if we can avoid the great throng of straw men wandering this way...

John Rumm

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Jun 23, 2015, 12:28:42 PM6/23/15

to

Remember you probably only play the lottery once or twice a week... you
use electricity in the home many times every day.

Robin

unread,

Jun 23, 2015, 1:38:29 PM6/23/15

to

John Rumm wrote:
>
> Probably depends on the area of the country... I would have thought a
> straight swap would start at £200 - £300.

I think that'd be v much the bottom of the range in London now the trade
has picked up again.

And then there are the "extras" like one place near here told they
needed *separate* main bonding for incoming gas and water. There was
10mm looped continuously MET-water-gas but the nice man even showed them
the picture in his little book to prove they needed to be separate :(

Harry Bloomfield

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Jun 23, 2015, 3:12:42 PM6/23/15

to

Jim x321x a écrit :
> Elderly an infirm people suddenly finding themselves walking around
> in pitch darkness, having to fumble their way to the CU. Surely that would
> be a dangersous situation for some, no? It would be interesting to know the
> statistics regarding how many people have suffered injury that way, vs. how
> many have suffered injury due to a fuse failing to blow, or a MCB failing
> to trip.

Indeed..

In the 1970's, I was with a crew working in a massive basement, several
hundreds of feet in size, pipes, obstructions, sumps and trip hazards
everywhere - installing massive pipes and pumps for a pumping station.
Total black out, even in full daylight outside. The site agent had
heard of RCD's and insisted everything be protected by a single RCD on
the 240v, which also supplied the 110v site transformer, which fed the
only lighting in the basement.

Every 10 minutes to an hour the RCD would trip out, leaving everyone in
complete darkness down there. Try explaining to a site agaent that the
risk of electrocution on a 55v to ground system is considerably less
than the risk of someone being seriously injured, with it tripping so
regularly leaving everyone in such circumstances in complete darkness,
feeling for the ladder to climb out.

tabb...@gmail.com

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Jun 23, 2015, 5:52:30 PM6/23/15

to

2 different issues lumped together, and a non sequitur. Maybe some of us just aren't into risk assessment.

NT

ARW

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Jun 23, 2015, 5:58:13 PM6/23/15

to

<tabb...@gmail.com> wrote in message
news:98916584-ba27-4e58...@googlegroups.com...

I do not consider telling a fat bastard to eat less less food to be DIY
related.

Fitting a lock on a fridge is DIY related.

--
Adam

tabb...@gmail.com

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Jun 23, 2015, 7:43:56 PM6/23/15

to

So what. A DIY safety improvement is only worth doing if its not way down the list of what one can usefully do. RCDs have their upside, but at 20 something deaths versus over 100,000 a year they're just not the priority. Eat healthily, learn advanced driving, treat infections promptly & vigilantly, take proper precautions with power tools and so on. If all those plus dozens of others are done, then an RCD becomes worthwhile.

Funny how so many think electricity & gas a big risk, when really the most dangerous things we do are food shopping & smoking.

NT

Jim x321x

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Jun 24, 2015, 5:59:29 AM6/24/15

to

Harry Bloomfield <harry...@tiscali.co.uk> wrote in
news:mmcb0m$s66$1...@dont-email.me:

> Every 10 minutes to an hour the RCD would trip out, leaving everyone
> in complete darkness down there. Try explaining to a site agaent that
> the risk of electrocution on a 55v to ground system is considerably
> less than the risk of someone being seriously injured, with it
> tripping so regularly leaving everyone in such circumstances in
> complete darkness, feeling for the ladder to climb out.
>

Sounds like a classic case of the 'Peter Pricipal' at play!

Can someone tell me if I can get away with a 45A MCB for a 8.5kW shower
without endagering life and limb? The manual tells me to use a 40A one, but
I just happen to have a 45A one. I ask, because those things aren't cheap.

Jim

ARW

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Jun 24, 2015, 2:52:47 PM6/24/15

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<tabb...@gmail.com> wrote in message
news:f7a4caa2-998a-4210...@googlegroups.com...

What is not so funny is how many people do not realise how dangerous
electrcity is.

It takes 20 to 30 years of smoking or shoveling chips down a big fat gob to
cause the damage. If they cannot see what is coming then it is their
problem - the NHS spend a fortune on preventative medicine and yet people
still live unhealthy lifestyles.

Electricity is unseen and kills in less than a second and may not be the
fault of the person that is killed. The IET have decided that RCD protection
is the future. It's not expensive and it saves lives - so much so that there
are thousands of people who did not receive the smallest of shocks when the
RCD operated saving them from becoming a minor statistic.

--
Adam

cupra

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Jun 24, 2015, 3:10:22 PM6/24/15

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John Rumm <see.my.s...@nowhere.null> wrote:
> On 22/06/2015 09:56, Jim x321x wrote:
>> John Rumm <see.my.s...@nowhere.null> wrote in
>> news:S8SdnWOCa5G-GxrI...@brightview.co.uk:
>>

>>>> with the existing setup, and I rarely get any inexplicable tripping
>>>> of the circuit breakers. As far as I am aware, the old fuse boxes
>>>> (even when fuses contained fuse wire) did what they were designed to
>>>> do, with no problems.
>>>
>>> They did what they were supposed to - and will still do so. The main
>>> thing your current setup lacks is RCD protection.
>>
>>
>> Thanks to all for the excellently helpful advice.
>>
>> If I added an RCD covering the entire house (without replacing the existing
>> fuse box which is already fitted with MCBs, would that constitute a change
>> to the wiring and thus require building control notification?
>
> Firstly you don't want a single RCD covering the whole house - that is a
> practice that was common during the 15th edition, but is deprecated now
> since it offers no "discrimination" in the event of a fault (i.e. the
> fault will take out the supply to the whole house, not just the circuit
> causing the problem). So many circuits on one RCD are also more prone to
> nuisance tripping in the first place.
>

> Changing a CU is "notifiable", although if done right no one is going to
> whinge if you don't.
>
>> Would doing this significantly improve the house's safety rating in the
>> eyes of, say, a house-purchaser's surveyor?
>
> Only if the purchaser is sufficiently clued up. You may find an older CU
> etc would be commented on during a survey, but only in as much as the
> surveyor might comment that you could get an electrical report if concerned.

>
> So if your only reason for the change is to make the house more saleable,
> I would not bother. If however you are planning to carry on living there,
> then its worth it (IMHO) for other reasons.
>

Just sold my house and survey recommended an electrical report, changing
the old fused CU was the result... (There was a hairline crack on the unit
as well, which didn't help)

ARW

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Jun 24, 2015, 3:16:31 PM6/24/15

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"cupra" <cupra....@gmail.com> wrote in message
news:1880965618456865627.7772...@news.individual.net...

--
Adam

tony sayer

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Jun 24, 2015, 4:45:21 PM6/24/15

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>What is not so funny is how many people do not realise how dangerous
>electrcity is.
>
>It takes 20 to 30 years of smoking or shoveling chips down a big fat gob to
>cause the damage. If they cannot see what is coming then it is their
>problem - the NHS spend a fortune on preventative medicine and yet people
>still live unhealthy lifestyles.
>
>Electricity is unseen and kills in less than a second and may not be the
>fault of the person that is killed. The IET have decided that RCD protection
>is the future. It's not expensive and it saves lives - so much so that there
>are thousands of people who did not receive the smallest of shocks when the
>RCD operated saving them from becoming a minor statistic.
>
>
>
>

I wish they were in common use around 35 years ago when I got "stuck"
across live to a less than correct earth on a metal handled drill;(...

Remember it to this day still, the pain and not being able to do anything
about it and that terror that this was going be my last day alive!:(

--
Tony Sayer

ARW

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Jun 27, 2015, 6:41:52 AM6/27/15

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John Rumm <see.my.s...@nowhere.null> wrote in

news:jqGdnTBtSrB16RDI...@brightview.co.uk:

> Subject: Re: Do I need to update my house's fuse box?
> From: John Rumm <see.my.s...@nowhere.null>
> Newsgroups: uk.d-i-y

Many thanks for the detailed reply. So what would be the ideal rating of
MCB to use? I just ordered a 40A one, because that's what the shower
manual recommends. The 45A one I had wasn't ideal because it wasn't a
Wylex one, and didn't fit without removing the base plate.

Jim

Johnny B Good

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Jun 27, 2015, 11:06:14 AM6/27/15

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In a nut shell, humanity's short sightedness when it comes to deciding
how we should spend effort and resources on tackling 'problems'. The
Green Party's obsession with wind turbine, solar voltaic and tidal
sources of energy is a classic case in point.

They regard these sources of Mother Nature's 'energy bounty' as being
'Low Tech' eco-friendly ways to solve the world population's energy
demands when they're anything but 'eco-friendly'.

They choose to ignore that other 'energy bounty' on offer from 'Mother
Nature', Nuclear Fission, on the basis that it requires ingenious high
tech methods of extraction involving, at the point of energy extraction,
highly dangerous radio active materials that have to be properly handled
and processed to reduce the risk to the environment at large by two or
three orders of magnitude compared to a conventional coal fired power
station of equivalent energy output.

Their thinking has been coloured by their experience of the earlier
nuclear powered station technologies driven by the needs of the cold war
demands to build up stocks of weapons' grade plutonium using power
stations sited in remote locations, seemingly to reduce the impact of a
Chernobyl like event on the population at large.

The plain fact is, it is now possible to upgrade existing coal fired
power stations to nuclear power, based on a Liquid Fueled Thorium Reactor
(LFTR) design that was first experimented with half a century ago as a
potential method of powering a USAF 'Always Aloft' Bomber Fleet.

Only the American Military had a big enough priority and the budget to
bankroll such 'Blue Sky' research projects. ICBMs sidelined the concept
of an always aloft bomber fleet so the technology, so promising a
solution as it was for civil nuclear power station design, was simply
left to languish.

If the 'Green Party' membership were to truly compare the *actual* cost/
benefit ratios of *all* the 'Green Options' Mother Nature Provides, LFTR
would win hands down on energy generation, environmental impact *and*
pollution costs. They wouldn't be able to tear down all those pointless
Wind Turbines fast enough!

Sadly, as you pointed out, it's humanity's propensity to short sighted
obsession with seemingly 'nice warm cozy 'cheap' 'feel good factor'
solutions that leads to wasted time and resources on sub-optimal
solutions. A shortsightedness that's invariably taken advantage of by the
"PT Barnum" "Get Rich Quick" type of individual or major corporate
business.

At the heart of all this, of course, is a nation's educational system
which, in the UK and America at least, is seriously lacking in teaching
the fundamental skills required to question gift horse offers and other
dubious claims such as that rather outrageous idea that the damaging
effects of nuclear radiation levels follow a totally contrary curve of
damage versus level which apply to all other forms of radiation exposure
such as UV light from solar radiation and the effects of microwave
radiation which have lead us into believing that almost impossibly
expensive anti-radiation precautions are required in Nuclear Power
Station design, making the Nuclear Power option infeasibly expensive.

Actually, the most expensive part of a Cold War type of Nuclear Power
Station is its Containment Vessel. A modern LFTR based design totally
does away with the need of such containment measures (along with an
expensive re-fueling process industry) whilst offering a 200 fold
improvement in energy yield from the nuclear fuel itself. As always,
"Ignorance"(tm) strikes again at the heart of the matter.

BTW, many a conspiracy theory nut would lay claim that the Oil and
Petrochemical industry are doing their best to scupper the idea of a
"Nuclear Powered World"(tm) when in fact it would be in their best
interests to branch out (diversify) into Nuclear Power Station design and
proliferation so they can corner the market in *synthesised*
petrochemicals and save the costs in dangerous exploration and drilling
for a dwindling natural resource.

--
Johnny B Good

John Rumm

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Jun 28, 2015, 1:09:46 AM6/28/15

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> Many thanks for the detailed reply. So what would be the ideal rating of
> MCB to use?

>= The nominal load on the circuit... so the next one up from 37A
(typically 40A)

> I just ordered a 40A one, because that's what the shower
> manual recommends. The 45A one I had wasn't ideal because it wasn't a
> Wylex one, and didn't fit without removing the base plate.
>
> Jim
>

John Rumm

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Jun 28, 2015, 1:50:57 AM6/28/15

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On 26/06/2015 19:54, tabb...@gmail.com wrote:
> On Friday, 26 June 2015 16:23:39 UTC+1, John Rumm wrote:

>>>> Not only that, as had been pointed out at various times, one
>>>> insures against losses that one can't otherwise replace. I
>>>> would include wife and children in that category, so a one off
>>>> premium of a couple of hundred for smoke alarms and RCDs sounds
>>>> like a very worthwhile investment.
>>>
>>> 2 different issues lumped together,
>>
>> Smoke alarms and RCDs are different - however the risks associated
>> with not having either are comparable (although injury from fires
>> per years are far fewer than from electric shock).
>
> 200 something deaths a year in fires now, 20 something from shock

I said injury, not deaths.

So we appear to be in agreement that deaths from either cause are very
low. Yet I don't hear you claiming fire protection systems including
smoke alarms are also a waste of money?

>> I seem to recall someone round here was very fond of plastering
>> domestic fire safety stats into every wiki article given the
>> chance. Why the double standards?
>
> why the claim of double standards? how would stating the known facts
> possibly be that? Its not even worth answering.

I feel like I am talking to a truculent five year old, with his fingers
in his ears, going ner ner, can't hear you.

You keep bleating on about death rates as justification for your
(absurd) position. And yet everyone acknowledges that the death rate
alone would not be a justification for wide spread use of RCDs (or smoke
alarms for that matter).

I am not suggesting that if one lives in a property without RCDs, they
you should be fitted because it will prevent someone from dying from
electrocution - even though that is true - the actual chances that you
will die that way are very small, and not worth the expense unless you
are, due to circumstances, at a higher than normal risk.

I am however suggesting that everyone who lives in a property without
RCD protection *should* update to include them as a resonable priority.
This is because *millions* of people receive electric shocks each year.
Hundreds of thousands of them require hospital treatment. Tens of
thousands of those receive a significant injury, many have ongoing and
debilitating effects.

RCDs represent a very cheap way of reducing a cause of injury that
affects a significant number of people in the country every year. There
are few widespread risks that are so easy to deal with in such a low
cost "fit and forget" way.

>>> and a non sequitur.
>>
>> Explain
>
> I already have. I've shown how I assessed whether RCDs were worth
> fitting.

Even if your logic were sound, that does not explain the "non sequiter"
claim.

You have carried out an assessment ignoring the most relevant parts of
the data, and focussed your attention on a very small subset.

> You simply did not address the necessary points in order to
> reach a reason based case on the question of whether its a good
> things to install your RCDs.
>
>>> Maybe some of us just aren't into risk assessment.
>>
>> You think... I wonder who?
>
> I've offered a clear risk & cost asessment,

Which only demonstrated you have failed to asses the facts.

> plus placed it in the
> list of available risk reductions, thereby determining if its a
> priority or whether there are far bigger priorities. Yours has so far
> been an assessment of the risk followed by an illogical conclusion.
> Unfortunately the approach you've shown is common today.

I agree that poor risk assessment is indeed common - its a part of human
nature and our evolution. We tend to greatly over estimate risks that
are perceived to be outside of our control, or that are newsworthy, and
imminent. While we tend to be complacent with risks that are familiar
and common, or only affect us in the very long term. Its why many people
fear flying, but not driving, worry about being raped in the street, but
not heart disease. Fear terrorism, but drive on bald tyres.

I don't agree that my assessment in this particular case is a
manifestation of this phenomenon.

> It results
> in people spending on tiny risks and consequently neglecting the big
> ones. No-one has the resources to address all risks, so the sensible
> approach is to prioritise the ones we can reduce the most.

I would agree with that.

> That is
> evidently not RCDs, unless you've effectively tackled a fairly long
> list of others already.

Much depends on what is on your list. Fix the loose stair carpet at the
top of the stairs, do something about the ancient boiler that makes you
feel all drowsy every time its fired up. If there is water running down
the walls, and mould everywhere you may have more urgent fish to fry.

spuorg...@gowanhill.com

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Jun 28, 2015, 6:53:44 AM6/28/15

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On Sunday, 28 June 2015 06:50:57 UTC+1, John Rumm wrote:
> If there is water running down
> the walls, and mould everywhere

... then RCD on the wiring is probably a very good idea in case your walls become live.

Owain