On Sat, 20 Jun 2015 19:34:39 +0100, Charles Hope wrote:

In article , Tough Guy no. 1265
wrote:
On Fri, 19 Jun 2015 19:59:55 +0100, charles
wrote:

In article , AL_n
wrote:
charles wrote in
:

Many thanks for that. Now for the dumb question! What is the max
wattage of electric shower I can use this for? Probably none, right?


do the maths - 8kW.


Thanks; that's encouraging. I'm not challenging your math, but the TLC
cable calculator below says says I'd need 10mm cable for an 8kw
shower. (same for a 7kw one). Perhaps they factor in some overkill to
cover themselves and/or perhaps make more profit? The length of my
cable run is 12metres.

Calculator I used is he

https://www.tlc-direct.co.uk/Technic...ltageDrop.html

12m is quite a long cable run for a shower, so yes, you might need a
thicker cable.

Voltage drop for 240V is negligible. It's how well insulated the run is
that matters, not the length.

The voltage drop will be the same for any voltage - it's dependant on
current. Insulation doesn't affect voltage drop.

As a percentage, the voltage drop is lower. If you had the same current at 12 volts, you could lose a sixth of the voltage with only 2 volts missing. 238 volts would be fine.

--
People who don't like their beliefs being laughed at shouldn't have such funny beliefs

On Saturday, 20 June 2015 16:51:34 UTC+1, John Rumm wrote:
Its a sellers market at the moment ;-)

I wish :-(

Owain

On 20/06/2015 21:17, wrote:
On Saturday, 20 June 2015 16:51:34 UTC+1, John Rumm wrote:
Its a sellers market at the moment ;-)

I wish :-(

Might be a different storey in jock land... ;-)


--
Cheers,

John.

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

On 20/06/2015 19:07, Andy Burns wrote:
AL_n wrote:

I cut off 200mm off one of the 7-strand wires, and after stripping,
it weighs 11g Can anyone tell me what the cable is now?

Seems equivalent to 6mm^2

http://www.wolframalpha.com/input/?i=11+grams+%2F+200mm+%2F+density+of+copper



Yes agree spot on.
Rough calc is:

11grams divide by 9 g/cm^3 = 1.2 cm^3 (cubic cms) = 1200 mm^3
1200 mm^3 divide by 200mm = 6 mm^2 cable.

Errors: even if 2g out on weight wouldnt take cable much below 5mm^2
which I dont think exists.

Accuracy could be improved by stripping other core and checking the
combined weight. Should of course be twice one core but would show up
any zeroing errors on scales.
Apologies for maths and experimental error lesson !!

"charles" wrote in message
...
In article , Brian Reay wrote:
On 19/06/15 17:54, AL_n wrote:
charles wrote in
:

I have some old white-covered twin & earth mains cable with its pos &
neg insulated in red & black.

The red & black wires are both 7-strand, and each individual strand
is about 1mm thick. Where all 7 strands are tightly together, the
total thickness of each pos or neg 7-strand cable is approx 3mm (not
including the red/black insulation).

The earth wire is single-strand and approx 1.5mm thick.

The overall outside dimensions of the cable (the white outer
covering) is:

13.5mm wide and 7.5mm thick.

It's probably 7/.044 which was rated at 36 A. 4.5mm is the metric
equivalent.

Many thanks for that. Now for the dumb question! What is the max
wattage of electric shower I can use this for? Probably none, right?

Al


My understanding is you should use the 'new colours' for new
installations. If you have the installation checked, and being a shower
you should, then you may have a problem.

I understand that if you mark the ends with the new colours then it is
permissable to use cable to the old spec.


There is no requirement to oversleeve old colours when being reused.

--
Adam

"charles" wrote in message
...
In article ,
AL_n wrote:
charles wrote in
:

Many thanks for that. Now for the dumb question! What is the max
wattage
of electric shower I can use this for? Probably none, right?


do the maths - 8kW.


Thanks; that's encouraging. I'm not challenging your math, but the TLC
cable calculator below says says I'd need 10mm cable for an 8kw shower.
(same for a 7kw one). Perhaps they factor in some overkill to cover
themselves and/or perhaps make more profit? The length of my cable run is
12metres.

Calculator I used is he

https://www.tlc-direct.co.uk/Technic...ltageDrop.html

12m is quite a long cable run for a shower, so yes, you might need a
thicker cable.

I would not be bothered by the distance but by the CCC due to the
installation method.



--
Adam

"AL_n" wrote in message
...
charles wrote in
:

Many thanks for that. Now for the dumb question! What is the max wattage
of electric shower I can use this for? Probably none, right?


do the maths - 8kW.


Thanks; that's encouraging. I'm not challenging your math, but the TLC
cable calculator below says says I'd need 10mm cable for an 8kw shower.
(same for a 7kw one). Perhaps they factor in some overkill to cover
themselves and/or perhaps make more profit? The length of my cable run is
12metres.

Calculator I used is he

https://www.tlc-direct.co.uk/Technic...ltageDrop.html


And the cable size is dependant on the installation method.

Re do the calc with a cable clipped to a wall and you can use 4.0mm T&E for
a 8kW shower



--
Adam

In article ,
ARW wrote:
I understand that if you mark the ends with the new colours then it is
permissable to use cable to the old spec.


There is no requirement to oversleeve old colours when being reused.

Is it allowed to use ancient cable such as this for what appears to be a
new part of an installation? Didn't the size of the ECC increase even
during the lifespan of metric? So any modern calculators etc ain't going
to be accurate?

--
*In "Casablanca", Humphrey Bogart never said "Play it again, Sam" *

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

"Dave Plowman (News)" wrote in message
...
In article ,
ARW wrote:
I understand that if you mark the ends with the new colours then it is
permissable to use cable to the old spec.


There is no requirement to oversleeve old colours when being reused.

Is it allowed to use ancient cable such as this for what appears to be a
new part of an installation? Didn't the size of the ECC increase even
during the lifespan of metric? So any modern calculators etc ain't going
to be accurate?


You are no longer supposed to install cables that use the old colours
(imperial or metric). You can certainly re-use ones that are already
installed as part of an alteration.

ECC = cpc :-)

It makes no difference that the cables are imperial as you would do the
calculations for the sizes you have - with a pen and paper if required -
"Please Sir can I use a calculator for the square root bit of the
calculation?"

As RCD protection will almost certainly be required for the OPs circuit then
a smaller cpc is irrelevant in this case. The RCD protects the cpc.

Regarding the increased size of cpcs in modern cables it is worth noting
that 2.5mmT&E did have it's cpc increased from 1.0mm to 1.5mm - I am not
aware of any other metric cables being changed. However this is probably due
to a ring circuit design fault (ie the one circuit that by default nearly
always uses 2.5mm T&E).

A final ring circuit that used the maximum length of 2.5mmT&E allowable for
voltage drop could not pass the adiabatic calculation with a 1.0mm cpc when
the protective device was a 30A rewireable fuse (the BS3036 ones).

Cheers

--
Adam

In article ,
ARW wrote:
Is it allowed to use ancient cable such as this for what appears to be
a new part of an installation? Didn't the size of the ECC increase
even during the lifespan of metric? So any modern calculators etc
ain't going to be accurate?


You are no longer supposed to install cables that use the old colours
(imperial or metric). You can certainly re-use ones that are already
installed as part of an alteration.

ECC = cpc :-)

It makes no difference that the cables are imperial as you would do the
calculations for the sizes you have - with a pen and paper if required -
"Please Sir can I use a calculator for the square root bit of the
calculation?"

Snag is the OP seems incapable of measuring a cable strand accurately -
and talked about using the TLC calculator.

As RCD protection will almost certainly be required for the OPs circuit
then a smaller cpc is irrelevant in this case. The RCD protects the cpc.

If you can be certain he'll use an RCD.

Regarding the increased size of cpcs in modern cables it is worth noting
that 2.5mmT&E did have it's cpc increased from 1.0mm to 1.5mm - I am
not aware of any other metric cables being changed. However this is
probably due to a ring circuit design fault (ie the one circuit that by
default nearly always uses 2.5mm T&E).


A final ring circuit that used the maximum length of 2.5mmT&E allowable
for voltage drop could not pass the adiabatic calculation with a 1.0mm
cpc when the protective device was a 30A rewireable fuse (the BS3036
ones).

Yup - that makes sense. Nudged my few remaining memory cells. ;-)

--
*Honk if you love peace and quiet.

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

On 21/06/2015 10:30, Robert wrote:

Yes agree spot on.
Rough calc is:

11grams divide by 9 g/cm^3 = 1.2 cm^3 (cubic cms) = 1200 mm^3
1200 mm^3 divide by 200mm = 6 mm^2 cable.

Yes, the sums look right but this doesn't fit in with the OP's
description of it having a single core cpc approx 1.5mm dia.

Looking at imperial cables in table 5 of my old 13th edition regs the
largest cable with a single core cpc is 3/036 but this can't be the case
here because we have 7 strand conductors.

A 1.5mm diameter conductor would have a cross section area of 1.77 mm^2
or 0.0027 in^2. This is close to the area of 0.003 in^2 required for a
cpc in 7/029 but I don't know if 7/029 with a single core earth ever
existed.

As others have said the only safe way will be to measure the conductor
sizes accurately to see if they match any of the standard sizes.

--
Mike Clarke

Mike Clarke wrote in
o.uk:

On 21/06/2015 10:30, Robert wrote:

Yes agree spot on.
Rough calc is:

11grams divide by 9 g/cm^3 = 1.2 cm^3 (cubic cms) = 1200 mm^3
1200 mm^3 divide by 200mm = 6 mm^2 cable.

Yes, the sums look right but this doesn't fit in with the OP's
description of it having a single core cpc approx 1.5mm dia.

Looking at imperial cables in table 5 of my old 13th edition regs the
largest cable with a single core cpc is 3/036 but this can't be the case
here because we have 7 strand conductors.

A 1.5mm diameter conductor would have a cross section area of 1.77 mm^2
or 0.0027 in^2. This is close to the area of 0.003 in^2 required for a
cpc in 7/029 but I don't know if 7/029 with a single core earth ever
existed.

As others have said the only safe way will be to measure the conductor
sizes accurately to see if they match any of the standard sizes.


If there are any psychic peeps reading this, please tell me where I put my
micrometer! I did compare my piece of stripped 7-core with the clean-cut
end of some 6mm T&E in Wickes today. It looks almost identical. It's
possible that my imperial 7-core is a few thou thicker. It's definitely not
thinner.

One thing that puzzled me a bit is that while the TLC site says that 7.5KW
is the most powerful shower you should run with 6mm^ cable, the blurb on
the side of a Wickes' shower box says it "recommends" using 10mm^ on
anything more than a 8.5kW shower. That seems to imply that I could use 6mm
cable for an 8.5kw shower. Any comments on that?

Al

"AL_n" wrote in
:



One thing that puzzled me a bit is that while the TLC site says that
7.5KW is the most powerful shower you should run with 6mm^ cable, the
blurb on the side of a Wickes' shower box says it "recommends" using
10mm^ on anything more than a 8.5kW shower. That seems to imply that I
could use 6mm cable for an 8.5kw shower. Any comments on that?



PS....

The table shown at the lnk below says much the same.

http://www.gainsboroughshowers.co.uk...le-Size-Chart/

So it looks like I could install an 8.5kw shower, assuming it's 6mm cable.
Anyone agree?

Al

"AL_n" wrote in message
...
"AL_n" wrote in
:



One thing that puzzled me a bit is that while the TLC site says that
7.5KW is the most powerful shower you should run with 6mm^ cable, the
blurb on the side of a Wickes' shower box says it "recommends" using
10mm^ on anything more than a 8.5kW shower. That seems to imply that I
could use 6mm cable for an 8.5kw shower. Any comments on that?



PS....

The table shown at the lnk below says much the same.

http://www.gainsboroughshowers.co.uk...le-Size-Chart/

So it looks like I could install an 8.5kw shower, assuming it's 6mm cable.
Anyone agree?


You could install a 10500W shower with 6mm cable if you did it properly.

The gainsborough link is not worth a toss.

--
Adam

AL_n wrote:

while the TLC site says that 7.5KW
is the most powerful shower you should run with 6mm^ cable, the blurb on
the side of a Wickes' shower box says it "recommends" using 10mm^ on
anything more than a 8.5kW shower. That seems to imply that I could use 6mm
cable for an 8.5kw shower. Any comments on that?

Depends, if everything was "ideal" you could even get away with 4mm^2
for 8.5kW. You've already told us the length, but not the fixing method
or any other factors that might require de-rating the cable (running in
or through insulation, grouping with other cables, etc) does it have
fuse or MCB, does it have RCD


Are you re-using an installed cable as some have asked, or hoping to use
some old cable you have knocking about? As there's still doubt whether
what you have is approx 6mm^2 or not, you could buy 10mm^2 cable for
under £2/m and give yourself a wider choice of shower ...

Andy Burns wrote in
o.uk:

while the TLC site says that 7.5KW
is the most powerful shower you should run with 6mm^ cable, the blurb
on the side of a Wickes' shower box says it "recommends" using 10mm^
on anything more than a 8.5kW shower. That seems to imply that I
could use 6mm cable for an 8.5kw shower. Any comments on that?

Depends, if everything was "ideal" you could even get away with 4mm^2
for 8.5kW. You've already told us the length, but not the fixing
method or any other factors that might require de-rating the cable
(running in or through insulation, grouping with other cables, etc)
does it have fuse or MCB, does it have RCD


Are you re-using an installed cable as some have asked, or hoping to
use some old cable you have knocking about? As there's still doubt
whether what you have is approx 6mm^2 or not, you could buy 10mm^2
cable for under œ2/m and give yourself a wider choice of shower ...


I've only been able to find 10mm cable for about £40 for 12m... If I can
get it for £2/m I might just do that.

The cable runs from the shower, up plastic trunking to the loft. It then
runs accross the loft (loose) and then down some plastic trunking to the
consumer unit which is an old type fuse box fitted with circuit-breakers.
It does not have RCD.

Al

"ARW" wrote in news:mm71mf$vdp$1@dont-
email.me:

You could install a 10500W shower with 6mm cable if you did it properly.

I must say, I just read some electrician saying he has "installed loads of
9.5kw showers on 6mm cable, and never had a problem".

Al

AL_n wrote:

I've only been able to find 10mm cable for about £40 for 12m... If I can
get it for £2/m I might just do that.

http://discount-electrical.co.uk/product.php/385718266

P&P extra, of course.

"AL_n" wrote in message
...
Andy Burns wrote in
o.uk:

while the TLC site says that 7.5KW
is the most powerful shower you should run with 6mm^ cable, the blurb
on the side of a Wickes' shower box says it "recommends" using 10mm^
on anything more than a 8.5kW shower. That seems to imply that I
could use 6mm cable for an 8.5kw shower. Any comments on that?

Depends, if everything was "ideal" you could even get away with 4mm^2
for 8.5kW. You've already told us the length, but not the fixing
method or any other factors that might require de-rating the cable
(running in or through insulation, grouping with other cables, etc)
does it have fuse or MCB, does it have RCD


Are you re-using an installed cable as some have asked, or hoping to
use some old cable you have knocking about? As there's still doubt
whether what you have is approx 6mm^2 or not, you could buy 10mm^2
cable for under o2/m and give yourself a wider choice of shower ...


I've only been able to find 10mm cable for about £40 for 12m... If I can
get it for £2/m I might just do that.

The cable runs from the shower, up plastic trunking to the loft. It then
runs accross the loft (loose) and then down some plastic trunking to the
consumer unit which is an old type fuse box fitted with circuit-breakers.



It does not have RCD.
^^^^^^^^^^^^^^^^^^^
That stops you fitting an electric shower.


--
Adam

In article ,
ARW wrote:
"AL_n" wrote in message
...
Andy Burns wrote in
o.uk:

while the TLC site says that 7.5KW
is the most powerful shower you should run with 6mm^ cable, the blurb
on the side of a Wickes' shower box says it "recommends" using 10mm^
on anything more than a 8.5kW shower. That seems to imply that I
could use 6mm cable for an 8.5kw shower. Any comments on that?

Depends, if everything was "ideal" you could even get away with 4mm^2
for 8.5kW. You've already told us the length, but not the fixing
method or any other factors that might require de-rating the cable
(running in or through insulation, grouping with other cables, etc)
does it have fuse or MCB, does it have RCD


Are you re-using an installed cable as some have asked, or hoping to
use some old cable you have knocking about? As there's still doubt
whether what you have is approx 6mm^2 or not, you could buy 10mm^2
cable for under o2/m and give yourself a wider choice of shower ...


I've only been able to find 10mm cable for about £40 for 12m... If I can
get it for £2/m I might just do that.

The cable runs from the shower, up plastic trunking to the loft. It
then runs accross the loft (loose) and then down some plastic trunking
to the consumer unit which is an old type fuse box fitted with
circuit-breakers.



It does not have RCD.
^^^^^^^^^^^^^^^^^^^
That stops you fitting an electric shower.

But you can add a "stand alone" RCD.

"ARW" wrote in news:mm73nl$7u3$1@dont-
email.me:

That stops you fitting an electric shower.

Well, I could swap the consumer unit for a MCB one, I suppose - or simply
add a shower mcb unit just for the shower, yes?

"Charles Hope" wrote in message
...
In article ,
ARW wrote:
"AL_n" wrote in message
...
Andy Burns wrote in
o.uk:

while the TLC site says that 7.5KW
is the most powerful shower you should run with 6mm^ cable, the blurb
on the side of a Wickes' shower box says it "recommends" using 10mm^
on anything more than a 8.5kW shower. That seems to imply that I
could use 6mm cable for an 8.5kw shower. Any comments on that?

Depends, if everything was "ideal" you could even get away with 4mm^2
for 8.5kW. You've already told us the length, but not the fixing
method or any other factors that might require de-rating the cable
(running in or through insulation, grouping with other cables, etc)
does it have fuse or MCB, does it have RCD


Are you re-using an installed cable as some have asked, or hoping to
use some old cable you have knocking about? As there's still doubt
whether what you have is approx 6mm^2 or not, you could buy 10mm^2
cable for under o2/m and give yourself a wider choice of shower ...


I've only been able to find 10mm cable for about £40 for 12m... If I
can
get it for £2/m I might just do that.

The cable runs from the shower, up plastic trunking to the loft. It
then runs accross the loft (loose) and then down some plastic trunking
to the consumer unit which is an old type fuse box fitted with
circuit-breakers.



It does not have RCD.
^^^^^^^^^^^^^^^^^^^
That stops you fitting an electric shower.

But you can add a "stand alone" RCD.

It's going to get messy if you want to meet the 17th edition regs.

I am all for DIY as long as it is done safely. Nothing the OP has posted so
far suggests that the electrical installation will be safe.

Let's start off with the main bonding - the first thing to be checked before
starting a shower installation (or indeed a shower swap)

--
Adam

"AL_n" wrote in message
...
"ARW" wrote in news:mm73nl$7u3$1@dont-
email.me:

That stops you fitting an electric shower.

Well, I could swap the consumer unit for a MCB one, I suppose - or simply
add a shower mcb unit just for the shower, yes?


It's RCD that you need

--
Adam

In article , ARW
o.uk scribeth thus
"AL_n" wrote in message
...
"AL_n" wrote in
:



One thing that puzzled me a bit is that while the TLC site says that
7.5KW is the most powerful shower you should run with 6mm^ cable, the
blurb on the side of a Wickes' shower box says it "recommends" using
10mm^ on anything more than a 8.5kW shower. That seems to imply that I
could use 6mm cable for an 8.5kw shower. Any comments on that?



PS....

The table shown at the lnk below says much the same.

http://www.gainsboroughshowers.co.uk...le-Size-Chart/

So it looks like I could install an 8.5kw shower, assuming it's 6mm cable.
Anyone agree?


You could install a 10500W shower with 6mm cable if you did it properly.

The gainsborough link is not worth a toss.


In fact the best thing you could install is a proper power shower and
just enjoy it

Best thing we ever did chucking the Electric ones!.


--
Tony Sayer

On 20/06/2015 14:00, John Rumm wrote:

You will have difficulty getting 2 x 6mm^2 into many junction boxes, so
look for one of the high current ones designed for the application.

Something like:

https://www.tlc-direct.co.uk/Products/LB9065.html

may be a better bet.

Or better still:

https://www.tlc-direct.co.uk/Products/AAJB60.html

(could not find that one on my first search - thanks to Adam for the
pointer!)


--
Cheers,

John.

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

"ARW" wrote in
:

Well, I could swap the consumer unit for a MCB one, I suppose - or
simply add a shower mcb unit just for the shower, yes?


It's RCD that you need

Sorry; that's what I meant.

"John Rumm" wrote in message
o.uk...
On 20/06/2015 14:00, John Rumm wrote:

You will have difficulty getting 2 x 6mm^2 into many junction boxes, so
look for one of the high current ones designed for the application.

Something like:

https://www.tlc-direct.co.uk/Products/LB9065.html

may be a better bet.

Or better still:

https://www.tlc-direct.co.uk/Products/AAJB60.html

(could not find that one on my first search - thanks to Adam for the
pointer!)

The best thing is that they have clamps for the cable.



--
Adam

"ARW" wrote in
:

Let's start off with the main bonding - the first thing to be checked
before starting a shower installation (or indeed a shower swap)

The house's copper gas supply pipe is bonded at the consumer unit. The
internal copper water pipes are bonded at the boiler which was recently
installed by British Gas engineers. The water pipe to the shower will be
plastic. It appears to be a TN-CS electric supply which installed in 1991.
I've nerver experienced any issues with the mains circuit.

tony sayer wrote in :


In fact the best thing you could install is a proper power shower and
just enjoy it

Best thing we ever did chucking the Electric ones!.

In my case, I wouldn't like a power shower because I have a combi boiler,
so every time I draw hot tapwater, the central heating cuts out. That's not
a problem in Summer, but in winter, it can be uncomfortable as the bathroom
grows cold pretty quickly when the central heating is cut off.

I've always likes electric showers, (Perfect water temperature, instantly,
etc) I've never had a problem with them - apart from one failing after
about ten years of use.

Al

John Rumm wrote in news:
:

https://www.tlc-direct.co.uk/Products/LB9065.html

may be a better bet.

Or better still:

https://www.tlc-direct.co.uk/Products/AAJB60.html

(could not find that one on my first search - thanks to Adam for the
pointer!)

Thanks for that. It turns out I will only need to make one join, so that's
good.

Al

On 21/06/2015 13:56, ARW wrote:

A final ring circuit that used the maximum length of 2.5mmT&E allowable
for voltage drop could not pass the adiabatic calculation with a 1.0mm
cpc when the protective device was a 30A rewireable fuse (the BS3036 ones).

If memory serves the circuit could pass, but any spur from it could fail...


--
Cheers,

John.

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

On 21/06/2015 20:30, AL_n wrote:

The cable runs from the shower, up plastic trunking to the loft. It then

Is this plastic trunking mounted on the surface of the wall, or buried
in it?

runs accross the loft (loose) and then down some plastic trunking to the
consumer unit which is an old type fuse box fitted with circuit-breakers.
It does not have RCD.

And the trunking there.. surface or buried?

Is your main equipotential bonding to current standards?

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




--
Cheers,

John.

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

John Rumm wrote in
o.uk:

The cable runs from the shower, up plastic trunking to the loft. It
then

Is this plastic trunking mounted on the surface of the wall, or buried
in it?

The trunking is mounted on the surface of the wall, inside the house.

runs accross the loft (loose) and then down some plastic trunking to
the consumer unit which is an old type fuse box fitted with
circuit-breakers. It does not have RCD.

And the trunking there.. surface or buried?

There is no trunking in the loft; the cable lies on the top of the glass
fibre loft insulation.

Is your main equipotential bonding to current standards?

I guess so, because a central heating system was installed a couple of
years ago, by well-trained British Gas engineers. I noticed they took a lot
of pains to make sure the bonding of their work was done properly. The
house's gas inlet pipe is also bonded directly to the CU's green+yellow
earth cable, whose overall thickness is 6mm. Where it is connected to the
gas mains supply pipe, there is an aluminium tag with a red stripe, saying
"Safety Electrical Connection Do Not Remove".

I guess it's all in order, but can I check the integrity of the earthing
and bonding somehow, say with a multi-meter?

Al

In article , AL_n
scribeth thus
tony sayer wrote in :


In fact the best thing you could install is a proper power shower and
just enjoy it

Best thing we ever did chucking the Electric ones!.

In my case, I wouldn't like a power shower because I have a combi boiler,
so every time I draw hot tapwater, the central heating cuts out. That's not
a problem in Summer, but in winter, it can be uncomfortable as the bathroom
grows cold pretty quickly when the central heating is cut off.


Simples chuck the combi;!..

I've always likes electric showers, (Perfect water temperature, instantly,
etc) I've never had a problem with them - apart from one failing after
about ten years of use.


Never had problems with someone else drawing water off elsewhere thus
changing the water feed pressure and the temp taking time to respond?..


Al

--
Tony Sayer

..

On 21/06/2015 21:49, AL_n wrote:
In my case, I wouldn't like a power shower because I have a combi boiler,
so every time I draw hot tapwater, the central heating cuts out. That's not
a problem in Summer, but in winter, it can be uncomfortable as the bathroom
grows cold pretty quickly when the central heating is cut off.

Ah that's the problem. You need a hot water tank. The boiler can then
heat more water at its leisure.

You can also use the immersion on days the boiler is having a sulk.

Andy

On 21/06/2015 16:56, Mike Clarke wrote:
On 21/06/2015 10:30, Robert wrote:

Yes agree spot on.
Rough calc is:

11grams divide by 9 g/cm^3 = 1.2 cm^3 (cubic cms) = 1200 mm^3
1200 mm^3 divide by 200mm = 6 mm^2 cable.

Yes, the sums look right but this doesn't fit in with the OP's
description of it having a single core cpc approx 1.5mm dia.

Why? The CPC in 6 mm^2 metric T&E is usually single strand 2.5 mm^2
(~1.78 mm dia).

I'm not sure why everybody's assumed that the OP's cable is imperial.
Are the conductors tinned copper or plain? IIRC imperial PVC cable to
BS 2004 continued to use tinned conductors (originally necessary with
rubber insulation). Plain copper only appeared at metrication, with the
introduction of BS 6004, c. 1969.

--
Andy

Andy Wade wrote in news:curemjFfli9U1
@mid.individual.net:

On 21/06/2015 16:56, Mike Clarke wrote:
On 21/06/2015 10:30, Robert wrote:

Yes agree spot on.
Rough calc is:

11grams divide by 9 g/cm^3 = 1.2 cm^3 (cubic cms) = 1200 mm^3
1200 mm^3 divide by 200mm = 6 mm^2 cable.

Yes, the sums look right but this doesn't fit in with the OP's
description of it having a single core cpc approx 1.5mm dia.

Why? The CPC in 6 mm^2 metric T&E is usually single strand 2.5 mm^2
(~1.78 mm dia).

I'm not sure why everybody's assumed that the OP's cable is imperial.
Are the conductors tinned copper or plain? IIRC imperial PVC cable to
BS 2004 continued to use tinned conductors (originally necessary with
rubber insulation). Plain copper only appeared at metrication, with the
introduction of BS 6004, c. 1969.


The wires within the cables in question look like copper through and
through. They are not coated in any silvery-looking metal such as tin.
The cables definitely look more recent than 1969, and are the same colour
of cables used to wire the entire house which was built in or around 1990.

Jim

Jim x321x wrote:

Andy Wade wrote:

Are the conductors tinned copper or plain?

The wires within the cables in question look like copper through and
through.

Confused ... is jim x321x the same person as AL_n? If so why do you
refer to yourself in the 3rd person as "someone" in the fuse box thread?

On 23/06/2015 10:00, Jim x321x wrote:

The wires within the cables in question look like copper through and
through. They are not coated in any silvery-looking metal such as tin.
The cables definitely look more recent than 1969, and are the same colour
of cables used to wire the entire house which was built in or around 1990.

I'd put money on it being 6 mm^2 then. '10-mil' would have a 7-strand
CPC. It could be '4-mil', but that size is much less commonly used,
especially in houses. If the CPC is the same size as the single strand
line & neutral conductors of 2.5 T&E, then it is 6 mm^2.

If you look at the sheath carefully you'll likely find that it's
embossed at intervals with the manufacturer's name, year of manufacture,
and sometimes the size.

--
Andy

In article ,
Andy Wade wrote:
I'm not sure why everybody's assumed that the OP's cable is imperial.
Are the conductors tinned copper or plain? IIRC imperial PVC cable to
BS 2004 continued to use tinned conductors (originally necessary with
rubber insulation). Plain copper only appeared at metrication, with the
introduction of BS 6004, c. 1969.

Plain copper PVC imperial was around. I've seen it.

There was also stranded metric 2.5mm - made IIRC in singles for conduit
use. But may have been made as a special in TW&E for say a particular
council - they could have odd ideas. And it's not expensive to have
special cable made provided you order enough.

--
*Is it true that cannibals don't eat clowns because they taste funny?

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