Metal backboxes complete with earth tail ?
 

If a metal backbox was supplied with a preinstalled piece of earth wire onto
the earth terminal, how much time do you think you could save 2nd fixing a
house ?

--
Ellis Greensitt, Site Admin, UK Electricians Forum
http://supplychain.org.uk/phpBB2/index.php

If a metal backbox was supplied with a preinstalled piece of earth wire
onto
the earth terminal, how much time do you think you could save 2nd fixing a
house ?

I'd guess about 30 seconds per fitting, or about 50 minutes on a big house.
However, I reckon you could save 15 seconds just by cutting the earth wires
in batch fashion, especially if done from a reel of insulated cable, rather
than uninsulated bits found lying about + separate sheath.

Christian.

"Ellis Greensitt" wrote in message
...
If a metal backbox was supplied with a preinstalled piece of earth wire
onto the earth terminal, how much time do you think you could save 2nd
fixing a house ?



More to the point, how much more likely would it be that the backbox would
be actually connected to the accessory plate! In the places I've lived in,
I haven't come across a single accessory plate that was properly earthed to
the backbox, until I've touched 'em that is.

I really like that idea. The incremental purchase cost surely can't be that
great, though a screw terminal would still have to be provided for the case
of the conductor becoming damaged or breaking off in the future.



--
Richard Sampson

mail me at
richard at olifant d-ot co do-t uk

In article ,
Ellis Greensitt wrote:
If a metal backbox was supplied with a preinstalled piece of earth wire
onto the earth terminal, how much time do you think you could save 2nd
fixing a house ?

It depends. Were you thinking of offering this? The trouble is whether
your time - or the person you pay to do it is worth less than an on site
sparks, since it can't easily be automated.
Also, would the person making these have to be certificated? ;-)

I quite liked the idea of pre-wired ceiling roses and pendant. But not all
houses have the same height ceilings.

--
*All men are idiots, and I married their King.

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

"Dave Plowman (News)" wrote in message
...
In article ,
Ellis Greensitt wrote:
If a metal backbox was supplied with a preinstalled piece of earth wire
onto the earth terminal, how much time do you think you could save 2nd
fixing a house ?

It depends. Were you thinking of offering this? The trouble is whether
your time - or the person you pay to do it is worth less than an on site
sparks, since it can't easily be automated.


for a manufacturer, it probably could be automated - provide a screw
terminal as before, but additionally crimp a length of insulated CPC onto a
different part of the back box.

It all comes down to price point & who does the first fit, really. If the
price is right & sparks do the first fit of back boxes then I reckon it'd be
a good selling point in a commodity marketplace, as long as the price
differential isn't great. If, however, general builders do the first fit,
then they won't care & will go for the cheapest product.

snip
--
Richard Sampson

mail me at
richard at olifant d-ot co do-t uk

In article ,
"Ellis Greensitt" writes:
If a metal backbox was supplied with a preinstalled piece of earth wire onto
the earth terminal, how much time do you think you could save 2nd fixing a
house ?

Sparks never earth back boxes, so it would add time to either connect
it or cut the wire off, neither of which they would otherwise do.
Also, it's another dangly bit to get in the plasterer's way.

Some conciensous DIY's earth back boxes, but their time is free to a
first approximation, so the time saved isn't worth anything.

--
Andrew Gabriel

This has sparked off a bit of a debate on the screwfix forum here
http://www.screwfix.com/talk/thread....19196&tstart=0

Leading to a vote on here

http://supplychain.org.uk/phpBB2/viewtopic.php?t=44

--
Ellis Greensitt, Site Admin, UK Electricians Forum
http://supplychain.org.uk/phpBB2/index.php

In article ,
Andrew Gabriel wrote:
If a metal backbox was supplied with a preinstalled piece of earth
wire onto the earth terminal, how much time do you think you could
save 2nd fixing a house ?

Sparks never earth back boxes, so it would add time to either connect
it or cut the wire off, neither of which they would otherwise do.
Also, it's another dangly bit to get in the plasterer's way.

They do, you know. Just sorted out a friend's new kitchen where a socket
wasn't working. Tail to the back box, but the neutral left so loose the
insulation had melted. And the line wasn't properly tightened either. Same
in all the other fittings.

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

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

Sparks never earth back boxes, so it would add time to either connect
it or cut the wire off, neither of which they would otherwise do.
Also, it's another dangly bit to get in the plasterer's way.

Some conciensous DIY's earth back boxes, but their time is free to a
first approximation, so the time saved isn't worth anything.

--
Andrew Gabriel[/quote]
More slagging off electricians and B*****it from Mr Gabriel, you must have a very shallow life or perhaps you need to get one!

On Mon, 13 Jun 2005 16:22:30 +0100, Ellis Greensitt wrote:

If a metal backbox was supplied with a preinstalled piece of earth wire onto
the earth terminal, how much time do you think you could save 2nd fixing a
house ?

AIUI the regulations _require_ the extra connection to the back box when
i) The earthing is supplied by the protective conduit. I.e. singles in
buried steel conduit.
ii) _Both_ the lugs on the back are movable (this is usually not the case
with most boxes in my experience.
iii) The countersunk eye of the fixing hole is only earthed on one side
(I've yet to see a socket like this - even the cheapest contract range)
and that side goes to the moveable lug.
iv) non conductive fixing screws are used.

I guess if the wire were pre-installed I would connect it up rather than
chop it off.


--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html

In article , Andrew Gabriel
wrote:

Sparks never earth back boxes, so it would add time to either connect
it or cut the wire off, neither of which they would otherwise do.
Also, it's another dangly bit to get in the plasterer's way.

Interesting. How about grommets in the cable entry holes?

--
AJL Electronics (G6FGO) Ltd : Satellite and TV aerial systems
http://www.classicmicrocars.co.uk : http://www.ajlelectronics.co.uk

In article ,
Andy Luckman (AJL Electronics) wrote:
Sparks never earth back boxes, so it would add time to either connect
it or cut the wire off, neither of which they would otherwise do.
Also, it's another dangly bit to get in the plasterer's way.

Interesting. How about grommets in the cable entry holes?

Rare without tails to the box earth. ;-)

--
*It IS as bad as you think, and they ARE out to get you.

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

In article ,
"Andy Luckman (AJL Electronics)" writes:
In article , Andrew Gabriel
wrote:

Sparks never earth back boxes, so it would add time to either connect
it or cut the wire off, neither of which they would otherwise do.
Also, it's another dangly bit to get in the plasterer's way.

Interesting. How about grommets in the cable entry holes?

It probably happens sometimes, but I don't recall seeing
missing grommets much in professional installs.

BTW, I wasn't claiming it was a requirement to always earth
a backbox -- it isn't unless it's exposed somehow.

--
Andrew Gabriel

In article , Andrew Gabriel
wrote:


BTW, I wasn't claiming it was a requirement to always earth
a backbox -- it isn't unless it's exposed somehow.

Well I have been doing it religiously. Can't find either of my two packs of
grommets though!

--
AJL Electronics (G6FGO) Ltd : Satellite and TV aerial systems
http://www.classicmicrocars.co.uk : http://www.ajlelectronics.co.uk

In article ,
"Andy Luckman (AJL Electronics)" writes:
In article , Andrew Gabriel
wrote:


BTW, I wasn't claiming it was a requirement to always earth
a backbox -- it isn't unless it's exposed somehow.

Well I have been doing it religiously. Can't find either of my two packs of
grommets though!

Well, grommets are probably a requirement as Good Workmanship,
unless you can achieve the same effect some other way.

I have occasionally used boxes which don't take grommets,
and have the holes pre-punched with the metal formed into
a smooth rounded lip (you couldn't fit a grommet even if
you wanted to). I had a number of these in a box of odds
and ends leftovers which have been knocking around for a
while, but I haven't seen them for sale anywhere recently,
and I can't remember where I originally bought them.

Also, recently I replastered and properly buried a lighting
cable into a wall which had been rather badly done in the
past. The box had oval entries and no grommets, and I had
no matching grommets. So instead, I pushed the oval trunking
right through the oval hole (for which it was an excellent
fit) and about a mm into the box, thereby protecting the
cable from any sharp metal edge.

As I've posted before, you can make grommet strip from the
outer sheath of T&E by stripping it off by running a knife
down the side of the earth conductor. A length cut this
way, and slightly over long so it's forcing itself to stay
in the hole, would be better than nothing in an emergency.

--
Andrew Gabriel

You can also buy grommet strip from places like rapid electronics:
http://tinyurl.com/9x6nu
which costs a fiver per five metre length.

Mungo

wrote in message
oups.com...
You can also buy grommet strip from places like rapid electronics:
http://tinyurl.com/9x6nu
which costs a fiver per five metre length.

Mungo

A bloody quid per metre? You're being ripped off mate. Local sparks
merchants will have grommet strip for around half that price.

In article ,
Andrew Gabriel wrote:
Well I have been doing it religiously. Can't find either of my two
packs of grommets though!

Well, grommets are probably a requirement as Good Workmanship,
unless you can achieve the same effect some other way.

If the box is mounted on brick, etc, and made good with plaster, there
ain't going to be any possibility of cable movement and therefore chafing.
However, since they only cost a couple of pence when bought by the
hundred, a sensible DIYer would use them as a matter of course.

--
*Fax is stronger than fiction *

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