Hi all

More of this electrickery stuff I'm afraid!

Looking on the TLC web site, there is text that states that an outdoor
socket must be on a dedicated 30mA RCD.
If this was fed from an existing kitchen ring, wouldn't there be a problem
with discrimination between the local socket protection and the circuit
protection at the CU? Is there an outdoor socket with integral RCD and can
I back-to-back this through an external wall with a kitchen socket IYSWIM?

Any comments on height of sockets above worktops? Googling suggests that
opinions are split either centering the sockets between worktop and
underside of wall cupboards or specifically not centering or doing something
that will marry with the tiles being used. As we aren't at tile choosing
stage, I don't want to hold things up waiting for that decision. Similar
with worktop thickness (still TBA), so approximate vertical centering is all
that is really possible.

One group member has suggested that, if I don't move the cooker point, then
I don't need to RCD it to bring it up to 17th edition spec. - any other
comments from the floor? I am working on the assumption that the install
will be inspected by BC appointed sparks, so these issues need to be correct
and Part P compliant.

Where I have cables through a cavity wall, I understand that a pipe or
conduit is required to protect these. What is recommended and is there a
split version that I can fit retrospectively (rather than disconnecting and
reconnecting exisiting equipment)?

I'm sure there were other points, but if I could remember them, the length
of the post would probably scare off the regulars!

TIA

Phil

"John Rumm" wrote in message
o.uk...
On 17/05/2010 09:18, TheScullster wrote:
Hi all

More of this electrickery stuff I'm afraid!

Looking on the TLC web site, there is text that states that an outdoor
socket must be on a dedicated 30mA RCD.

It needs to be 30mA - not sure it has to be dedicated. However...

If this was fed from an existing kitchen ring, wouldn't there be a
problem
with discrimination between the local socket protection and the circuit
protection at the CU? Is there an outdoor socket with integral RCD and
can
I back-to-back this through an external wall with a kitchen socket
IYSWIM?

There is a good case for not having outdoor sockets etc not sharing a RCD
with inside ones. Since it increases the liklihood of getting nuisance
trips on your house circuits.

Where possible it is best practice to try and put the outside sockets on
their own RCBO. If that is not possible then I try to power them via a
double pole switch so that if they do let water in then they can be isolated
without causing any problems.

There is no requirement for them to have their own dedicated RCD.


Any comments on height of sockets above worktops? Googling suggests that
opinions are split either centering the sockets between worktop and
underside of wall cupboards or specifically not centering or doing
something
that will marry with the tiles being used. As we aren't at tile choosing
stage, I don't want to hold things up waiting for that decision. Similar
with worktop thickness (still TBA), so approximate vertical centering is
all
that is really possible.

Roughly centre works for me, but go with whatever the management deems
most desirable ;-)

I still put them 6 inchs above the worktop unless otherwise instructed.

If it don't line up with the tiles, then that's just an excuse to get a
nice lekky tile cutter!

vbg.


One group member has suggested that, if I don't move the cooker point,
then
I don't need to RCD it to bring it up to 17th edition spec. - any other
comments from the floor? I am working on the assumption that the install

A bit more detail would help... i.e. what is there now, do you need it at
all? Does it need moving etc.

will be inspected by BC appointed sparks, so these issues need to be
correct
and Part P compliant.

Might be worth clarifying with BC what they are anticipating. Technically
speaking a part P sparks can only do the work and self certify - they
can't certify someone else's work. (However BC may be happy with a sparks
just testing / inspecting and reporting on someone else's work - or they
may even be happy with accepting your test results if they get the
impression you know what you are doing).

Where I have cables through a cavity wall, I understand that a pipe or
conduit is required to protect these. What is recommended and is there a

Not necessarily. Cables should be either:

I assumed that Phil was talking about passing a cable through a cavity for
the outside socket! If so then use a bit of plastic pipe if you want to.
Personally I just pass the cable through the hole.


Cheers

Adam

"ARWadsworth" wrote in message
...

Any comments on height of sockets above worktops? Googling suggests
that
opinions are split either centering the sockets between worktop and
underside of wall cupboards or specifically not centering or doing
something
that will marry with the tiles being used. As we aren't at tile
choosing
stage, I don't want to hold things up waiting for that decision.
Similar
with worktop thickness (still TBA), so approximate vertical centering is
all
that is really possible.

Roughly centre works for me, but go with whatever the management deems
most desirable ;-)

I still put them 6 inchs above the worktop unless otherwise instructed.

That's 6 inches from the worktop to the bottom of the back box.

Adam

"John Rumm" wrote in message
o.uk...
On 17/05/2010 09:18, TheScullster wrote:
Hi all

More of this electrickery stuff I'm afraid!

Looking on the TLC web site, there is text that states that an outdoor
socket must be on a dedicated 30mA RCD.

It needs to be 30mA - not sure it has to be dedicated. However...

I'm struggling to refind the link now

If this was fed from an existing kitchen ring, wouldn't there be a
problem
with discrimination between the local socket protection and the circuit
protection at the CU? Is there an outdoor socket with integral RCD and
can
I back-to-back this through an external wall with a kitchen socket
IYSWIM?

There is a good case for not having outdoor sockets etc not sharing a RCD
with inside ones. Since it increases the liklihood of getting nuisance
trips on your house circuits.

That I can see, but unfortunately I'm not in a position to route another
dedicated feed through.

There is no point in having cascaded RCDs though[1], since as you rightly
suspect you can't predict whether one or both will trip, and if its one,
then which.

[1] The exception being when the upstream one is a type S device with a
time delay.

Any comments on height of sockets above worktops? Googling suggests that
opinions are split either centering the sockets between worktop and
underside of wall cupboards or specifically not centering or doing
something
that will marry with the tiles being used. As we aren't at tile choosing
stage, I don't want to hold things up waiting for that decision. Similar
with worktop thickness (still TBA), so approximate vertical centering is
all
that is really possible.

Roughly centre works for me, but go with whatever the management deems
most desirable ;-)

Yes I always ask the questions in advance, but it doesn't necessarly absolve
me of responsibility unfortunately.

If it don't line up with the tiles, then that's just an excuse to get a
nice lekky tile cutter!

Hmm yes I have been pondering that idea!

One group member has suggested that, if I don't move the cooker point,
then
I don't need to RCD it to bring it up to 17th edition spec. - any other
comments from the floor? I am working on the assumption that the install

A bit more detail would help... i.e. what is there now, do you need it at
all? Does it need moving etc.

Yes I need it exactly where it is now.


will be inspected by BC appointed sparks, so these issues need to be
correct
and Part P compliant.

Might be worth clarifying with BC what they are anticipating. Technically
speaking a part P sparks can only do the work and self certify - they
can't certify someone else's work. (However BC may be happy with a sparks
just testing / inspecting and reporting on someone else's work - or they
may even be happy with accepting your test results if they get the
impression you know what you are doing).

BC are supposed to inspect at first fix and then test on completion as part
of the building notice AIUI - unless the goal posts have moved (again) of
course.

Where I have cables through a cavity wall, I understand that a pipe or
conduit is required to protect these. What is recommended and is there a

Not necessarily. Cables should be either:

Buried = 50mm from the surface, or
Protected by an earthed screen of some form (i.e. earthshild, SWA, MICC,
Steel conduit etc), or
protected by a 30mA trip RCD.

split version that I can fit retrospectively (rather than disconnecting
and
reconnecting exisiting equipment)?

Adding RCD protection is the easiest retrofit in most cases.

Had intended fitting RCBOs to the affected circuits but they won't fit in my
Clipsal box

I'm sure there were other points, but if I could remember them, the
length
of the post would probably scare off the regulars!

Do we look like the type to be scared by a few words ;-)

On the strength of your previous posts I would say you were the most
unlikely.

Thanks John

Phil

On Mon, 17 May 2010 17:35:27 +0100 someone who may be Dave Osborne
wrote this:-

When the regs (for supplementary bonding) first came out, they were
either a bit wishy washy or all-encompassing (I forget which), so in a
belt-and-braces, cover-your-arse kind of knee-jerk response, it became
the done thing to supplementary bond every little piece of extraneous
metal in any location with running water.

They were gold plated by some/many. It was always clear that if some
metalwork could introduce a potential in a location then its
resistance to earth should be measured and it should only be bonded
if necessary.



--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000...#pt3-pb3-l1g54

In article ,
"TheScullster" writes:

"John Rumm" wrote in message
o.uk...
On 17/05/2010 09:18, TheScullster wrote:
Hi all

More of this electrickery stuff I'm afraid!

Looking on the TLC web site, there is text that states that an outdoor
socket must be on a dedicated 30mA RCD.

It needs to be 30mA - not sure it has to be dedicated. However...

I'm struggling to refind the link now

It can be less than 30mA too. My outdoor socket circuit has
a 10mA RCBO.

If this was fed from an existing kitchen ring, wouldn't there be a
problem
with discrimination between the local socket protection and the circuit
protection at the CU? Is there an outdoor socket with integral RCD and
can
I back-to-back this through an external wall with a kitchen socket
IYSWIM?

There is a good case for not having outdoor sockets etc not sharing a RCD
with inside ones. Since it increases the liklihood of getting nuisance
trips on your house circuits.

That I can see, but unfortunately I'm not in a position to route another
dedicated feed through.

Include a double pole switch so you can isolate the outdoor circuit
from indoors, in the event it gets wet and stops you keeping the
indoor circuit on. You might also leave it switched off to stop
someone else connecting appliances to it (which is why I have one
even though it's a dedicated circuit). Actually, what works well
for me is a cooker switch with integral socket in the garage, the
cooker switch controlling the outdoor sockets (suitably relabeled).

Might be worth clarifying with BC what they are anticipating. Technically
speaking a part P sparks can only do the work and self certify - they
can't certify someone else's work. (However BC may be happy with a sparks
just testing / inspecting and reporting on someone else's work - or they
may even be happy with accepting your test results if they get the
impression you know what you are doing).

BC are supposed to inspect at first fix and then test on completion as part
of the building notice AIUI - unless the goal posts have moved (again) of
course.

That's entirely up to them. There's no requirement for them to test
anything in Part P - that's just them gold plating the rules.
It was originally envisaged that it would be a simple visual check
by the BCO, not requiring specifically qualified electricians.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

TheScullster wrote:
"John Rumm" wrote in message
o.uk...
On 17/05/2010 09:18, TheScullster wrote:

Any comments on height of sockets above worktops? Googling suggests that
opinions are split either centering the sockets between worktop and
underside of wall cupboards or specifically not centering or doing something
that will marry with the tiles being used. As we aren't at tile choosing
stage, I don't want to hold things up waiting for that decision. Similar
with worktop thickness (still TBA), so approximate vertical centering is
all that is really possible.

Roughly centre works for me, but go with whatever the management deems
most desirable ;-)

Yes I always ask the questions in advance, but it doesn't necessarly absolve
me of responsibility unfortunately.

If it don't line up with the tiles, then that's just an excuse to get a
nice lekky tile cutter!

Hmm yes I have been pondering that idea!

I think the main issue to consider when setting the socket position is
what size tiles you'll be using... if you get it wrong you can end up
with just a sliver of tile at the edge of the socket, which looks really
****e. Same issue applies to the horizontal position of the sockets,
although bad tile cuts are usually easier to circumvent then.

David