Discussion:
Wiring a fused spur.
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Roger Hayter
2024-05-08 11:55:13 UTC
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I want to wire a fused spur from a UPS in one room to a double socket (BS1363)
in the next room for convenience in transferring telephone and IP equipment
from mains to UPS. Because of existing holes in the wall and trunking I want
to wire it with 1mm^2 T&E. Given it is supplied via a marked 3A fused double
pole switch, is this ok?
--
Roger Hayter
Theo
2024-05-08 12:16:15 UTC
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Permalink
Post by Roger Hayter
I want to wire a fused spur from a UPS in one room to a double socket (BS1363)
in the next room for convenience in transferring telephone and IP equipment
from mains to UPS. Because of existing holes in the wall and trunking I want
to wire it with 1mm^2 T&E. Given it is supplied via a marked 3A fused double
pole switch, is this ok?
Is this wired from the house wiring, or from the output of the UPS?

If it's a spur off the ring then the TLC calculator says you can go up to
80m in 1mm2 with a 3A load. The 3A fused connection unit will ensure you
don't overload the ring.

If it's from the output of the UPS then it's more or less a wall mounted
extension lead. The UPS will limit the output current.

There's a bunch of stuff in 18th edition Amendment 2 [which I don't have]
about 'prosumers' where you are both consuming and generating power - think
solar inverters and batteries. I think technically the UPS would count as
one of those, but if you're not backfeeding or mixing with the house wiring
then I don't think it's significnat here - you're just making a longer wire
from the socket on your UPS. I would ensure that any such trailing socket
is isolated from other electrical systems - eg don't wire the earth of such
a socket to any other earth, and don't share socket boxes with your mains
supply.

Theo
Roger Hayter
2024-05-08 12:29:15 UTC
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Post by Theo
Post by Roger Hayter
I want to wire a fused spur from a UPS in one room to a double socket (BS1363)
in the next room for convenience in transferring telephone and IP equipment
from mains to UPS. Because of existing holes in the wall and trunking I want
to wire it with 1mm^2 T&E. Given it is supplied via a marked 3A fused double
pole switch, is this ok?
Is this wired from the house wiring, or from the output of the UPS?
If it's a spur off the ring then the TLC calculator says you can go up to
80m in 1mm2 with a 3A load. The 3A fused connection unit will ensure you
don't overload the ring.
If it's from the output of the UPS then it's more or less a wall mounted
extension lead. The UPS will limit the output current.
There's a bunch of stuff in 18th edition Amendment 2 [which I don't have]
about 'prosumers' where you are both consuming and generating power - think
solar inverters and batteries. I think technically the UPS would count as
one of those, but if you're not backfeeding or mixing with the house wiring
then I don't think it's significnat here - you're just making a longer wire
from the socket on your UPS. I would ensure that any such trailing socket
is isolated from other electrical systems - eg don't wire the earth of such
a socket to any other earth, and don't share socket boxes with your mains
supply.
Theo
Yes, and at the UPS end the connection is one of those trailing IEC
kettle-type sockets which cannot be inadvertently plugged into the mains. I
always worry about people replacing the 3A fuse with a 13A one. I think spurs
should be supplied with a choice of permanently marked fuse holders. The UPS
could theoretically supply up to 6A into an inductive load (1500VA) but not
for long.
--
Roger Hayter
Smolley
2024-05-08 12:38:41 UTC
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Permalink
On 8 May 2024 at 13:16:15 BST, "Theo"
Post by Theo
Post by Roger Hayter
I want to wire a fused spur from a UPS in one room to a double socket (BS1363)
in the next room for convenience in transferring telephone and IP
equipment from mains to UPS. Because of existing holes in the wall and
trunking I want to wire it with 1mm^2 T&E. Given it is supplied via a
marked 3A fused double pole switch, is this ok?
Is this wired from the house wiring, or from the output of the UPS?
If it's a spur off the ring then the TLC calculator says you can go up
to 80m in 1mm2 with a 3A load. The 3A fused connection unit will
ensure you don't overload the ring.
If it's from the output of the UPS then it's more or less a wall
mounted extension lead. The UPS will limit the output current.
There's a bunch of stuff in 18th edition Amendment 2 [which I don't
have] about 'prosumers' where you are both consuming and generating
power - think solar inverters and batteries. I think technically the
UPS would count as one of those, but if you're not backfeeding or
mixing with the house wiring then I don't think it's significnat here -
you're just making a longer wire from the socket on your UPS. I would
ensure that any such trailing socket is isolated from other electrical
systems - eg don't wire the earth of such a socket to any other earth,
and don't share socket boxes with your mains supply.
Theo
Yes, and at the UPS end the connection is one of those trailing IEC
kettle-type sockets which cannot be inadvertently plugged into the
mains. I always worry about people replacing the 3A fuse with a 13A one.
I think spurs should be supplied with a choice of permanently marked
fuse holders. The UPS could theoretically supply up to 6A into an
inductive load (1500VA) but not for long.
I thought you was a radio ham.
Theo
2024-05-09 10:40:27 UTC
Reply
Permalink
Post by Theo
There's a bunch of stuff in 18th edition Amendment 2 [which I don't have]
about 'prosumers' where you are both consuming and generating power - think
solar inverters and batteries. I think technically the UPS would count as
one of those, but if you're not backfeeding or mixing with the house wiring
then I don't think it's significnat here - you're just making a longer wire
from the socket on your UPS. I would ensure that any such trailing socket
is isolated from other electrical systems - eg don't wire the earth of such
a socket to any other earth, and don't share socket boxes with your mains
supply.
Turns out Amendment 2 specifically excludes UPSes as a 'Prosumer Electrical
Installation' (PEI):

823 PEI CONCEPT
[...]
An uninterruptible power supply (UPS) is not considered to form part of a
PEI as the purpose of a UPS is only to supply downstream critical loads and
is not capable of reverse feeding the public network and/or current-using
equipment in the upstream part of the installation.


So as it says, as long as you keep the UPS output separate from your mains
electrical system it's a standalone thing and not covered by BS7671.

Theo
Roger Hayter
2024-05-11 11:24:21 UTC
Reply
Permalink
Post by Theo
Post by Theo
There's a bunch of stuff in 18th edition Amendment 2 [which I don't have]
about 'prosumers' where you are both consuming and generating power - think
solar inverters and batteries. I think technically the UPS would count as
one of those, but if you're not backfeeding or mixing with the house wiring
then I don't think it's significnat here - you're just making a longer wire
from the socket on your UPS. I would ensure that any such trailing socket
is isolated from other electrical systems - eg don't wire the earth of such
a socket to any other earth, and don't share socket boxes with your mains
supply.
Turns out Amendment 2 specifically excludes UPSes as a 'Prosumer Electrical
823 PEI CONCEPT
[...]
An uninterruptible power supply (UPS) is not considered to form part of a
PEI as the purpose of a UPS is only to supply downstream critical loads and
is not capable of reverse feeding the public network and/or current-using
equipment in the upstream part of the installation.
So as it says, as long as you keep the UPS output separate from your mains
electrical system it's a standalone thing and not covered by BS7671.
Theo
That's very reassuring - thanks for looking it up!
--
Roger Hayter
Alan Lee
2024-05-08 12:27:08 UTC
Reply
Permalink
Post by Roger Hayter
I want to wire a fused spur from a UPS in one room to a double socket (BS1363)
in the next room for convenience in transferring telephone and IP equipment
from mains to UPS. Because of existing holes in the wall and trunking I want
to wire it with 1mm^2 T&E. Given it is supplied via a marked 3A fused double
pole switch, is this ok?
In real world use, it will be fine, but it will not meet BS7671, as
power conductors need to be a minimum of 1.5mm for the live conductors.
Be aware tapping off from a socket that already has 2 x 2.5mm cables in
it is not great, the 1mm can easily slip out, no mater how tight you
screw it down, so it will need doubling over. To do it properly, just
use 2.5mm T+E.
Roger Hayter
2024-05-08 12:35:41 UTC
Reply
Permalink
Post by Alan Lee
Post by Roger Hayter
I want to wire a fused spur from a UPS in one room to a double socket (BS1363)
in the next room for convenience in transferring telephone and IP equipment
from mains to UPS. Because of existing holes in the wall and trunking I want
to wire it with 1mm^2 T&E. Given it is supplied via a marked 3A fused double
pole switch, is this ok?
In real world use, it will be fine, but it will not meet BS7671, as
power conductors need to be a minimum of 1.5mm for the live conductors.
Be aware tapping off from a socket that already has 2 x 2.5mm cables in
it is not great, the 1mm can easily slip out, no mater how tight you
screw it down, so it will need doubling over. To do it properly, just
use 2.5mm T+E.
It isn't connected to a ring, just to the o/p of a UPS. But I am not sure if I
can get 1.5mm T&E into my existing trunking. The route I am using currently
carries redundant telephone extension wiring. Is BS7671 a mechanical or
electrical specification? I suppose I could put ferrules on the 1mm
conductors? Or Wagoes in the backbox?
--
Roger Hayter
Roger Hayter
2024-05-08 12:42:16 UTC
Reply
Permalink
Post by Roger Hayter
Post by Alan Lee
Post by Roger Hayter
I want to wire a fused spur from a UPS in one room to a double socket (BS1363)
in the next room for convenience in transferring telephone and IP equipment
from mains to UPS. Because of existing holes in the wall and trunking I want
to wire it with 1mm^2 T&E. Given it is supplied via a marked 3A fused double
pole switch, is this ok?
In real world use, it will be fine, but it will not meet BS7671, as
power conductors need to be a minimum of 1.5mm for the live conductors.
Be aware tapping off from a socket that already has 2 x 2.5mm cables in
it is not great, the 1mm can easily slip out, no mater how tight you
screw it down, so it will need doubling over. To do it properly, just
use 2.5mm T+E.
It isn't connected to a ring, just to the o/p of a UPS. But I am not sure if I
can get 1.5mm T&E into my existing trunking. The route I am using currently
carries redundant telephone extension wiring. Is BS7671 a mechanical or
electrical specification? I suppose I could put ferrules on the 1mm
conductors? Or Wagoes in the backbox?
Drilling the hole in the wall out bigger is not easy, because the fairly loose
irregular slate stones tend to slip out of place and jam large masonry bits
which act more as jack hammers than drills and not good for your wrists if
they jam.
--
Roger Hayter
SteveW
2024-05-09 11:07:21 UTC
Reply
Permalink
Post by Roger Hayter
Post by Roger Hayter
Post by Alan Lee
Post by Roger Hayter
I want to wire a fused spur from a UPS in one room to a double socket (BS1363)
in the next room for convenience in transferring telephone and IP equipment
from mains to UPS. Because of existing holes in the wall and trunking I want
to wire it with 1mm^2 T&E. Given it is supplied via a marked 3A fused double
pole switch, is this ok?
In real world use, it will be fine, but it will not meet BS7671, as
power conductors need to be a minimum of 1.5mm for the live conductors.
Be aware tapping off from a socket that already has 2 x 2.5mm cables in
it is not great, the 1mm can easily slip out, no mater how tight you
screw it down, so it will need doubling over. To do it properly, just
use 2.5mm T+E.
It isn't connected to a ring, just to the o/p of a UPS. But I am not sure if I
can get 1.5mm T&E into my existing trunking. The route I am using currently
carries redundant telephone extension wiring. Is BS7671 a mechanical or
electrical specification? I suppose I could put ferrules on the 1mm
conductors? Or Wagoes in the backbox?
Drilling the hole in the wall out bigger is not easy, because the fairly loose
irregular slate stones tend to slip out of place and jam large masonry bits
which act more as jack hammers than drills and not good for your wrists if
they jam.
It's well worth getting an SDS drill with a built-in clutch - I did just
that, some years ago, when I needed to core drill a vent hole, while
standing on a ladder. My existing mains drill would have done the job,
but I feared for my wrist and for my stability on the ladder, without
that safety clutch. With it, there is very little kick-back.
RJH
2024-05-09 13:11:19 UTC
Reply
Permalink
<div id="editor" contenteditable="false">> Drilling the hole in the wall out
bigger is not easy, because the fairly loose
Post by Roger Hayter
irregular slate stones tend to slip out of place and jam large masonry bits
which act more as jack hammers than drills and not good for your wrists if
they jam.
It's well worth getting an SDS drill with a built-in clutch - I did just
that, some years ago, when I needed to core drill a vent hole, while
standing on a ladder. My existing mains drill would have done the job,
but I feared for my wrist and for my stability on the ladder, without
that safety clutch. With it, there is very little kick-back.
I've just drilled a 52mm hole through a cavity wall, using an SDS and diamond
core bit. I'm not sure if the bricks are especially hard or the bit poor
quality, but there's no way I could have done it from a ladder. Took about 2
hours, heavy work.
--
Cheers, Rob, Sheffield UK
SteveW
2024-05-09 13:49:04 UTC
Reply
Permalink
Post by RJH
<div id="editor" contenteditable="false">> Drilling the hole in the wall out
bigger is not easy, because the fairly loose
Post by Roger Hayter
irregular slate stones tend to slip out of place and jam large masonry bits
which act more as jack hammers than drills and not good for your wrists if
they jam.
It's well worth getting an SDS drill with a built-in clutch - I did just
that, some years ago, when I needed to core drill a vent hole, while
standing on a ladder. My existing mains drill would have done the job,
but I feared for my wrist and for my stability on the ladder, without
that safety clutch. With it, there is very little kick-back.
I've just drilled a 52mm hole through a cavity wall, using an SDS and diamond
core bit. I'm not sure if the bricks are especially hard or the bit poor
quality, but there's no way I could have done it from a ladder. Took about 2
hours, heavy work.
It sound like the bit. Even hard-bricks don't normally take that long.

The vent was a 5" hole, just below the 1st floor eaves and with a very
heavy SDS drill ... it was very hard work. I have done others from
inside (this one was in too tight a space for that), but sometimes up on
a step ladder.

So far, one bathroom vent, one toilet vent, two soil pipes, seven waste
pipes, one tumble dryer vent, one cooker hood vent, three underfloor
vents, one boiler flue and one condensate drain. I think my SDS has more
than paid for itself, without including any of the other things I've
used it for or any time its been used somewhere other than at home.
RJH
2024-05-10 15:08:04 UTC
Reply
Permalink
Post by SteveW
Post by RJH
<div id="editor" contenteditable="false">> Drilling the hole in the wall out
bigger is not easy, because the fairly loose
Post by Roger Hayter
irregular slate stones tend to slip out of place and jam large masonry bits
which act more as jack hammers than drills and not good for your wrists if
they jam.
It's well worth getting an SDS drill with a built-in clutch - I did just
that, some years ago, when I needed to core drill a vent hole, while
standing on a ladder. My existing mains drill would have done the job,
but I feared for my wrist and for my stability on the ladder, without
that safety clutch. With it, there is very little kick-back.
I've just drilled a 52mm hole through a cavity wall, using an SDS and diamond
core bit. I'm not sure if the bricks are especially hard or the bit poor
quality, but there's no way I could have done it from a ladder. Took about 2
hours, heavy work.
It sound like the bit. Even hard-bricks don't normally take that long.
Could be - it was a medium-cheap from Toolstation. The drill is a 1kW Lidl -
seems good and the clutch works.

On hindsight - and this isn't that well thought through - I reckon drill a
10mm pilot from inside, then carry on inside right through to within a couple
of inches. Then finish off the last bit from the outside, using the pilot hole
as guide.
Post by SteveW
The vent was a 5" hole, just below the 1st floor eaves and with a very
heavy SDS drill ... it was very hard work. I have done others from
inside (this one was in too tight a space for that), but sometimes up on
a step ladder.
So far, one bathroom vent, one toilet vent, two soil pipes, seven waste
pipes, one tumble dryer vent, one cooker hood vent, three underfloor
vents, one boiler flue and one condensate drain. I think my SDS has more
than paid for itself, without including any of the other things I've
used it for or any time its been used somewhere other than at home.
Good grief - that's good going!
--
Cheers, Rob, Sheffield UK
SteveW
2024-05-11 11:03:25 UTC
Reply
Permalink
Post by RJH
Post by SteveW
Post by RJH
<div id="editor" contenteditable="false">> Drilling the hole in the wall out
bigger is not easy, because the fairly loose
Post by Roger Hayter
irregular slate stones tend to slip out of place and jam large masonry bits
which act more as jack hammers than drills and not good for your wrists if
they jam.
It's well worth getting an SDS drill with a built-in clutch - I did just
that, some years ago, when I needed to core drill a vent hole, while
standing on a ladder. My existing mains drill would have done the job,
but I feared for my wrist and for my stability on the ladder, without
that safety clutch. With it, there is very little kick-back.
I've just drilled a 52mm hole through a cavity wall, using an SDS and diamond
core bit. I'm not sure if the bricks are especially hard or the bit poor
quality, but there's no way I could have done it from a ladder. Took about 2
hours, heavy work.
It sound like the bit. Even hard-bricks don't normally take that long.
Could be - it was a medium-cheap from Toolstation. The drill is a 1kW Lidl -
seems good and the clutch works.
On hindsight - and this isn't that well thought through - I reckon drill a
10mm pilot from inside, then carry on inside right through to within a couple
of inches. Then finish off the last bit from the outside, using the pilot hole
as guide.
Post by SteveW
The vent was a 5" hole, just below the 1st floor eaves and with a very
heavy SDS drill ... it was very hard work. I have done others from
inside (this one was in too tight a space for that), but sometimes up on
a step ladder.
So far, one bathroom vent, one toilet vent, two soil pipes, seven waste
pipes, one tumble dryer vent, one cooker hood vent, three underfloor
vents, one boiler flue and one condensate drain. I think my SDS has more
than paid for itself, without including any of the other things I've
used it for or any time its been used somewhere other than at home.
Good grief - that's good going!
Just rearrangements of the bathroom and kitchen, addition of a second
toilet and fitting underground under-floor vent pipes before pouring a
slab for a conservatory. It's amazing how many things need holes through
the walls.
alan_m
2024-05-09 14:03:14 UTC
Reply
Permalink
Post by RJH
<div id="editor" contenteditable="false">> Drilling the hole in the wall out
bigger is not easy, because the fairly loose
Post by Roger Hayter
irregular slate stones tend to slip out of place and jam large masonry bits
which act more as jack hammers than drills and not good for your wrists if
they jam.
It's well worth getting an SDS drill with a built-in clutch - I did just
that, some years ago, when I needed to core drill a vent hole, while
standing on a ladder. My existing mains drill would have done the job,
but I feared for my wrist and for my stability on the ladder, without
that safety clutch. With it, there is very little kick-back.
I've just drilled a 52mm hole through a cavity wall, using an SDS and diamond
core bit. I'm not sure if the bricks are especially hard or the bit poor
quality, but there's no way I could have done it from a ladder. Took about 2
hours, heavy work.
The only time I've had that kind of trouble with core drill was I
inadvertently had the core turning the wrong way.
Clockwise/anticlockwise is too easy to change on my Dewalt SDS. :(
--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk
RJH
2024-05-10 15:13:22 UTC
Reply
Permalink
Post by alan_m
Post by RJH
<div id="editor" contenteditable="false">> Drilling the hole in the wall out
bigger is not easy, because the fairly loose
Post by Roger Hayter
irregular slate stones tend to slip out of place and jam large masonry bits
which act more as jack hammers than drills and not good for your wrists if
they jam.
It's well worth getting an SDS drill with a built-in clutch - I did just
that, some years ago, when I needed to core drill a vent hole, while
standing on a ladder. My existing mains drill would have done the job,
but I feared for my wrist and for my stability on the ladder, without
that safety clutch. With it, there is very little kick-back.
I've just drilled a 52mm hole through a cavity wall, using an SDS and diamond
core bit. I'm not sure if the bricks are especially hard or the bit poor
quality, but there's no way I could have done it from a ladder. Took about 2
hours, heavy work.
The only time I've had that kind of trouble with core drill was I
inadvertently had the core turning the wrong way.
Clockwise/anticlockwise is too easy to change on my Dewalt SDS. :(
I did think that and checked. Weird thing was when I tried it counterclockwise
for some reason, it suddenly appeared to cut though an inch or so. Not sure
what that was about. Couldn't use it that way for long in any case - the core
bit would simply unscrew from the shank. Don't ask how I know :-)
--
Cheers, Rob, Sheffield UK
John Rumm
2024-05-13 11:53:45 UTC
Reply
Permalink
Post by RJH
<div id="editor" contenteditable="false">> Drilling the hole in the wall out
bigger is not easy, because the fairly loose
Post by Roger Hayter
irregular slate stones tend to slip out of place and jam large masonry bits
which act more as jack hammers than drills and not good for your wrists if
they jam.
It's well worth getting an SDS drill with a built-in clutch - I did just
that, some years ago, when I needed to core drill a vent hole, while
standing on a ladder. My existing mains drill would have done the job,
but I feared for my wrist and for my stability on the ladder, without
that safety clutch. With it, there is very little kick-back.
I've just drilled a 52mm hole through a cavity wall, using an SDS and diamond
core bit. I'm not sure if the bricks are especially hard or the bit poor
quality, but there's no way I could have done it from a ladder. Took about 2
hours, heavy work.
One tip that can help, is that once the core is started, take the pilot
bit out of the end of the core - quite often drilling the pilot with no
hammer action in hard material is very slow.

(I normally stick a pilot hole through with a 10mm SDS bit first to
check the exit point. Then use that to run the core pilot for getting
the core started. Then take the pilot out once going (otherwise it can
vibrate loose since it is not actually pushing against anything)
--
Cheers,

John.

/=================================================================\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\=================================================================/
Tricky Dicky
2024-05-15 15:18:41 UTC
Reply
Permalink
Post by John Rumm
Post by RJH
<div id="editor" contenteditable="false">> Drilling the hole in the wall out
bigger is not easy, because the fairly loose
Post by Roger Hayter
irregular slate stones tend to slip out of place and jam large masonry bits
which act more as jack hammers than drills and not good for your wrists if
they jam.
It's well worth getting an SDS drill with a built-in clutch - I did just
that, some years ago, when I needed to core drill a vent hole, while
standing on a ladder. My existing mains drill would have done the job,
but I feared for my wrist and for my stability on the ladder, without
that safety clutch. With it, there is very little kick-back.
I've just drilled a 52mm hole through a cavity wall, using an SDS and diamond
core bit. I'm not sure if the bricks are especially hard or the bit poor
quality, but there's no way I could have done it from a ladder. Took about 2
hours, heavy work.
One tip that can help, is that once the core is started, take the pilot
bit out of the end of the core - quite often drilling the pilot with no
hammer action in hard material is very slow.
(I normally stick a pilot hole through with a 10mm SDS bit first to
check the exit point. Then use that to run the core pilot for getting
the core started. Then take the pilot out once going (otherwise it can
vibrate loose since it is not actually pushing against anything)
Some Core drill sets come with a guide rod which enables you to drill a
pilot hole straight though with a normal SDS drill. The guide rod then
helps guide the core drill along the pilot hole. This is useful if you want
to core drill from both sides and align the holes.

Roger Hayter
2024-05-11 11:25:48 UTC
Reply
Permalink
Post by SteveW
Post by Roger Hayter
Post by Roger Hayter
Post by Alan Lee
Post by Roger Hayter
I want to wire a fused spur from a UPS in one room to a double socket (BS1363)
in the next room for convenience in transferring telephone and IP equipment
from mains to UPS. Because of existing holes in the wall and trunking I want
to wire it with 1mm^2 T&E. Given it is supplied via a marked 3A fused double
pole switch, is this ok?
In real world use, it will be fine, but it will not meet BS7671, as
power conductors need to be a minimum of 1.5mm for the live conductors.
Be aware tapping off from a socket that already has 2 x 2.5mm cables in
it is not great, the 1mm can easily slip out, no mater how tight you
screw it down, so it will need doubling over. To do it properly, just
use 2.5mm T+E.
It isn't connected to a ring, just to the o/p of a UPS. But I am not sure if I
can get 1.5mm T&E into my existing trunking. The route I am using currently
carries redundant telephone extension wiring. Is BS7671 a mechanical or
electrical specification? I suppose I could put ferrules on the 1mm
conductors? Or Wagoes in the backbox?
Drilling the hole in the wall out bigger is not easy, because the fairly loose
irregular slate stones tend to slip out of place and jam large masonry bits
which act more as jack hammers than drills and not good for your wrists if
they jam.
It's well worth getting an SDS drill with a built-in clutch - I did just
that, some years ago, when I needed to core drill a vent hole, while
standing on a ladder. My existing mains drill would have done the job,
but I feared for my wrist and for my stability on the ladder, without
that safety clutch. With it, there is very little kick-back.
I think that's very good advice - it is rarely in the specs of cheap ones, I
suppose I have to buy a well known make!
--
Roger Hayter
SteveW
2024-05-11 19:46:21 UTC
Reply
Permalink
Post by Roger Hayter
Post by SteveW
Post by Roger Hayter
Post by Roger Hayter
Post by Alan Lee
Post by Roger Hayter
I want to wire a fused spur from a UPS in one room to a double socket (BS1363)
in the next room for convenience in transferring telephone and IP equipment
from mains to UPS. Because of existing holes in the wall and trunking I want
to wire it with 1mm^2 T&E. Given it is supplied via a marked 3A fused double
pole switch, is this ok?
In real world use, it will be fine, but it will not meet BS7671, as
power conductors need to be a minimum of 1.5mm for the live conductors.
Be aware tapping off from a socket that already has 2 x 2.5mm cables in
it is not great, the 1mm can easily slip out, no mater how tight you
screw it down, so it will need doubling over. To do it properly, just
use 2.5mm T+E.
It isn't connected to a ring, just to the o/p of a UPS. But I am not sure if I
can get 1.5mm T&E into my existing trunking. The route I am using currently
carries redundant telephone extension wiring. Is BS7671 a mechanical or
electrical specification? I suppose I could put ferrules on the 1mm
conductors? Or Wagoes in the backbox?
Drilling the hole in the wall out bigger is not easy, because the fairly loose
irregular slate stones tend to slip out of place and jam large masonry bits
which act more as jack hammers than drills and not good for your wrists if
they jam.
It's well worth getting an SDS drill with a built-in clutch - I did just
that, some years ago, when I needed to core drill a vent hole, while
standing on a ladder. My existing mains drill would have done the job,
but I feared for my wrist and for my stability on the ladder, without
that safety clutch. With it, there is very little kick-back.
I think that's very good advice - it is rarely in the specs of cheap ones, I
suppose I have to buy a well known make!
Mine's just a cheap Titan from Screwfix.
Tim Lamb
2024-05-11 20:05:08 UTC
Reply
Permalink
Post by SteveW
Post by Roger Hayter
Post by SteveW
Post by Roger Hayter
Post by Roger Hayter
Post by Alan Lee
Post by Roger Hayter
I want to wire a fused spur from a UPS in one room to a double socket (BS1363)
in the next room for convenience in transferring telephone and IP equipment
from mains to UPS. Because of existing holes in the wall and trunking I want
to wire it with 1mm^2 T&E. Given it is supplied via a marked 3A fused double
pole switch, is this ok?
In real world use, it will be fine, but it will not meet BS7671, as
power conductors need to be a minimum of 1.5mm for the live conductors.
Be aware tapping off from a socket that already has 2 x 2.5mm cables in
it is not great, the 1mm can easily slip out, no mater how tight you
screw it down, so it will need doubling over. To do it properly, just
use 2.5mm T+E.
It isn't connected to a ring, just to the o/p of a UPS. But I am not sure if I
can get 1.5mm T&E into my existing trunking. The route I am using currently
carries redundant telephone extension wiring. Is BS7671 a mechanical or
electrical specification? I suppose I could put ferrules on the 1mm
conductors? Or Wagoes in the backbox?
Drilling the hole in the wall out bigger is not easy, because the fairly loose
irregular slate stones tend to slip out of place and jam large masonry bits
which act more as jack hammers than drills and not good for your wrists if
they jam.
It's well worth getting an SDS drill with a built-in clutch - I did just
that, some years ago, when I needed to core drill a vent hole, while
standing on a ladder. My existing mains drill would have done the job,
but I feared for my wrist and for my stability on the ladder, without
that safety clutch. With it, there is very little kick-back.
I think that's very good advice - it is rarely in the specs of cheap ones, I
suppose I have to buy a well known make!
Mine's just a cheap Titan from Screwfix.
Hmm. I have a corded DeWalt SDS. Does a job but the clutch slips:-(
--
Tim Lamb
John Rumm
2024-05-13 11:56:41 UTC
Reply
Permalink
Post by Tim Lamb
Post by SteveW
Post by SteveW
Post by Roger Hayter
Post by Roger Hayter
Post by Alan Lee
Post by Roger Hayter
I want to wire a fused spur from a UPS in one room to a double
socket (BS1363)
in the next room for convenience in transferring telephone and IP equipment
from mains to UPS. Because of existing holes in the wall and trunking I want
to wire it with 1mm^2 T&E. Given it is supplied via a marked 3A fused double
pole switch, is this ok?
In real world use, it will be fine, but it will not meet BS7671, as
power conductors need to be a minimum of 1.5mm for the live conductors.
Be aware tapping off from a socket that already has 2 x 2.5mm cables in
it is not great, the 1mm can easily slip out, no mater how tight you
screw it down, so it will need doubling over. To do it properly, just
use 2.5mm T+E.
It isn't connected to a ring, just to the o/p of a UPS. But I am not sure if I
can get 1.5mm T&E into my existing trunking. The route I am using currently
carries redundant telephone extension wiring. Is BS7671 a
mechanical or
electrical specification? I suppose I could put ferrules on the 1mm
conductors? Or Wagoes in the backbox?
Drilling the hole in the wall out bigger is not easy, because the fairly loose
irregular slate stones tend to slip out of place and jam large masonry bits
which act more as jack hammers than drills and not good for your wrists if
they jam.
It's well worth getting an SDS drill with a built-in clutch - I did just
that, some years ago, when I needed to core drill a vent hole, while
standing on a ladder. My existing mains drill would have done the job,
but I feared for my wrist and for my stability on the ladder, without
that safety clutch. With it, there is very little kick-back.
 I think that's very good advice - it is rarely in the specs of cheap
ones, I
suppose I have to buy a well known make!
Mine's just a cheap Titan from Screwfix.
Hmm. I have a corded DeWalt SDS. Does a job but the clutch slips:-(
SDS clutches are not usually set at a level that is ideal for larger
core bits. In an "easy" wall they are usually fine, but it a hard / damp
one, just spinning the core at all can be difficult IME.

(TBH, my dedicated core drill is not much better - I but I think that is
a fault of the drill!)
--
Cheers,

John.

/=================================================================\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\=================================================================/
John Rumm
2024-05-08 15:53:36 UTC
Reply
Permalink
Post by Roger Hayter
Post by Alan Lee
Post by Roger Hayter
I want to wire a fused spur from a UPS in one room to a double socket (BS1363)
in the next room for convenience in transferring telephone and IP equipment
from mains to UPS. Because of existing holes in the wall and trunking I want
to wire it with 1mm^2 T&E. Given it is supplied via a marked 3A fused double
pole switch, is this ok?
In real world use, it will be fine, but it will not meet BS7671, as
power conductors need to be a minimum of 1.5mm for the live conductors.
Be aware tapping off from a socket that already has 2 x 2.5mm cables in
it is not great, the 1mm can easily slip out, no mater how tight you
screw it down, so it will need doubling over. To do it properly, just
use 2.5mm T+E.
It isn't connected to a ring, just to the o/p of a UPS. But I am not sure if I
can get 1.5mm T&E into my existing trunking.
If you have trunking you could wire that in singles rather than T&E,
which will give you much more space to play with.
Post by Roger Hayter
The route I am using currently
carries redundant telephone extension wiring. Is BS7671 a mechanical or
electrical specification?
BS7671 (aka "The Wiring Regs" is principally an electrical spec - but
touches lots of bases on mechanical, thermal, emc/emi etc.

I suppose I could put ferrules on the 1mm
Post by Roger Hayter
conductors? Or Wagoes in the backbox?
Yup you can also get sockets these days with wago style terminals built
in instead of traditional screw terminals.
--
Cheers,

John.

/=================================================================\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\=================================================================/
Scott
2024-05-08 14:24:13 UTC
Reply
Permalink
Post by Roger Hayter
I want to wire a fused spur from a UPS in one room to a double socket (BS1363)
in the next room for convenience in transferring telephone and IP equipment
from mains to UPS. Because of existing holes in the wall and trunking I want
to wire it with 1mm^2 T&E. Given it is supplied via a marked 3A fused double
pole switch, is this ok?
What about using a Schuko socket? That would certainly discourage
anyone plugging is some other UK appliance (like the vacuum cleaner).
Roger Hayter
2024-05-11 11:32:04 UTC
Reply
Permalink
Post by Scott
Post by Roger Hayter
I want to wire a fused spur from a UPS in one room to a double socket (BS1363)
in the next room for convenience in transferring telephone and IP equipment
from mains to UPS. Because of existing holes in the wall and trunking I want
to wire it with 1mm^2 T&E. Given it is supplied via a marked 3A fused double
pole switch, is this ok?
What about using a Schuko socket? That would certainly discourage
anyone plugging is some other UK appliance (like the vacuum cleaner).
A good idea, and I could do it if I used a short adapter/extension lead with a
Shuko plug and a couple of BS1363 sockets for the wallwarts. I may not,
because really only the UPS is going to suffer with a large overload, and the
sockets won't even be live after I'm dead and gone and the UPS disconnected.
--
Roger Hayter
John Rumm
2024-05-08 15:49:47 UTC
Reply
Permalink
Post by Roger Hayter
I want to wire a fused spur from a UPS in one room to a double socket (BS1363)
in the next room for convenience in transferring telephone and IP equipment
from mains to UPS. Because of existing holes in the wall and trunking I want
to wire it with 1mm^2 T&E. Given it is supplied via a marked 3A fused double
pole switch, is this ok?
Since this is fed from the output of the UPS and not direct from the
mains, it is arguably not even fixed wiring in the conventional sense.
So the 1mm^2 will have adequate fault protection by the 3A fuse.

(and the UPS itself will likely have overload protection)
--
Cheers,

John.

/=================================================================\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\=================================================================/
Roger Hayter
2024-05-11 11:33:38 UTC
Reply
Permalink
Post by John Rumm
Post by Roger Hayter
I want to wire a fused spur from a UPS in one room to a double socket (BS1363)
in the next room for convenience in transferring telephone and IP equipment
from mains to UPS. Because of existing holes in the wall and trunking I want
to wire it with 1mm^2 T&E. Given it is supplied via a marked 3A fused double
pole switch, is this ok?
Since this is fed from the output of the UPS and not direct from the
mains, it is arguably not even fixed wiring in the conventional sense.
So the 1mm^2 will have adequate fault protection by the 3A fuse.
(and the UPS itself will likely have overload protection)
That was my reasoning, but I will see if 1.5mm will fit. Glad to see you
agree!
--
Roger Hayter
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