While I was on the TLC website I was doing a thought experiment.

Twin and earth cable comes in a variety of sizes:
1, 1.5, 2.5, 4, 6, 10, 16 mm2.

But what if you want to wire three phase? TLC only have 1 and 1.5mm2 three
core and earth. Doncaster Cables also have 2.5mm2 but not larger. CEF
likewise. There's some three core in SWA but I assume that's primarily for
external use?

I understand that using three phase you can get 3x the power compared to
single phase - so a 32A radial would get you 7.3kW single phase or 22kW
three phase.

But how should you wire that? For a 32A single phase radial the TLC
calculator indicates it needs 6mm2. What cable do you use for three phase?

I suppose you could run a pair of 4/6/10mm2 T&E but that would seem
'surprising' - one of those pairs carries two phases instead of live and
neutral, and anyone who mixes up a phase for neutral may be in for a shock.
Plus the colour scheme is confusing (two brown and two blue, which phase is
which again? You can sleeve, but what if you mix up the cables?)

You could use SWA, but that's fairly unwieldy and pricey for an internal
installation.

So what's the 'proper' way to do it?

Thanks
Theo

On 06/02/2021 23:14, Theo wrote:
While I was on the TLC website I was doing a thought experiment.

Twin and earth cable comes in a variety of sizes:
1, 1.5, 2.5, 4, 6, 10, 16 mm2.

But what if you want to wire three phase? TLC only have 1 and 1.5mm2 three
core and earth. Doncaster Cables also have 2.5mm2 but not larger. CEF
likewise. There's some three core in SWA but I assume that's primarily for
external use?

I understand that using three phase you can get 3x the power compared to
single phase - so a 32A radial would get you 7.3kW single phase or 22kW
three phase.

But how should you wire that? For a 32A single phase radial the TLC
calculator indicates it needs 6mm2. What cable do you use for three phase?

I suppose you could run a pair of 4/6/10mm2 T&E but that would seem
'surprising' - one of those pairs carries two phases instead of live and
neutral, and anyone who mixes up a phase for neutral may be in for a shock.
Plus the colour scheme is confusing (two brown and two blue, which phase is
which again? You can sleeve, but what if you mix up the cables?)

You could use SWA, but that's fairly unwieldy and pricey for an internal
installation.

So what's the 'proper' way to do it?

Thanks
Theo

IME at the domestic / light industrial level 3 phase is usually wired in
single core.

On Saturday, 6 February 2021 at 23:15:02 UTC, Theo wrote:
While I was on the TLC website I was doing a thought experiment.

Twin and earth cable comes in a variety of sizes:
1, 1.5, 2.5, 4, 6, 10, 16 mm2.

But what if you want to wire three phase? TLC only have 1 and 1.5mm2 three
core and earth. Doncaster Cables also have 2.5mm2 but not larger. CEF
likewise. There's some three core in SWA but I assume that's primarily for
external use?

I understand that using three phase you can get 3x the power compared to
single phase - so a 32A radial would get you 7.3kW single phase or 22kW
three phase.

But how should you wire that? For a 32A single phase radial the TLC
calculator indicates it needs 6mm2. What cable do you use for three phase?

I suppose you could run a pair of 4/6/10mm2 T&E but that would seem
'surprising' - one of those pairs carries two phases instead of live and
neutral, and anyone who mixes up a phase for neutral may be in for a shock.
Plus the colour scheme is confusing (two brown and two blue, which phase is
which again? You can sleeve, but what if you mix up the cables?)

You could use SWA, but that's fairly unwieldy and pricey for an internal
installation.

So what's the 'proper' way to do it?

Thanks
Theo

You could go to a "proper" supplier but are you really planning to install a three phase circuit in a domestic property or just shooting the breeze?

On 06/02/2021 23:43, Steve Walker wrote:
On 06/02/2021 23:20, newshound wrote:
On 06/02/2021 23:14, Theo wrote:
While I was on the TLC website I was doing a thought experiment.

Twin and earth cable comes in a variety of sizes:
1, 1.5, 2.5, 4, 6, 10, 16 mm2.

But what if you want to wire three phase?Â* TLC only have 1 and 1.5mm2
three
core and earth.Â* Doncaster Cables also have 2.5mm2 but not larger.Â* CEF
likewise.Â* There's some three core in SWA but I assume that's
primarily for
external use?

I understand that using three phase you can get 3x the power compared to
single phase - so a 32A radial would get you 7.3kW single phase or 22kW
three phase.

But how should you wire that?Â* For a 32A single phase radial the TLC
calculator indicates it needs 6mm2.Â* What cable do you use for three
phase?

I suppose you could run a pair of 4/6/10mm2 T&E but that would seem
'surprising' - one of those pairs carries two phases instead of live and
neutral, and anyone who mixes up a phase for neutral may be in for a
shock.
Plus the colour scheme is confusing (two brown and two blue, which
phase is
which again?Â* You can sleeve, but what if you mix up the cables?)

You could use SWA, but that's fairly unwieldy and pricey for an internal
installation.

So what's the 'proper' way to do it?

Thanks
Theo

IME at the domestic / light industrial level 3 phase is usually wired in
single core.

And for heavier industrial use, you could use something like:

https://www.vwcable.com/nyy-nyy-j-ny...h-power-cable/

Although the biggest I have seen myself (while testing a gas turbine
generator set) used singles - 3 pairs of 500mm2

Somewhat coincidentally, and further to the thread which I started last
week with the subject "At what low mains voltages do devices stop
working?", there have been two 500kVA generators running locally while
work was being done on a substation (I thought one was 300kVA as it was
smaller than the other, but was informed by a guy from SSE that both
were 500kVA). Both had 5 cables from them, four were yellow and seemed
to be about 25mm diameter, the other was yellow with a green stripe and
was somewhat less - maybe 20mm in diameter. A rather poor close-up photo
of connections made to the overhead line (440V?) is shown he
https://ibb.co/vBgFpj3
I think it is possible to just make out the colours, and assume the
other ends hidden in the generator are also colour coded. Does the earth
carry less current, or it it just there in case the neutral fails as a
temporary backup?

I guess those 25 mm cables have about 300 - 350mm^2 wire in them, and
are rated at 500 - 1000A.

Not far form me is a house with a Tesla parked in the drive. There is a
shoe-box sized wall charger unit with a cable about 20 - 25 mm diameter
going into it. I assume that's 3-phase.

--

Jeff

Theo wrote:

For a 32A single phase radial the TLC
calculator indicates it needs 6mm2. What cable do you use for three phase?

There are "lighter" 3-ph cables than SWA, where armour protection isn't
needed (e.g. server rooms) e.g SY flex, or tuff sheathed

https://www.doncastercables.com/cables/5/10/Control-Cable/SY-Steel-Wire-Braid-Flexible-PVC-Control-Cable/

https://www.doncastercables.com/cables/6/24/SWA-and-Mains-Distribution/XLPE-Insulated--PVC-Bedded-and-Tuf-Sheathed-Non-Armoured-Cables/

On 07/02/2021 09:11, Andy Burns wrote:
Theo wrote:

For a 32A single phase radial the TLC
calculator indicates it needs 6mm2.Â* What cable do you use for three
phase?

There are "lighter" 3-ph cables than SWA, where armour protection isn't
needed (e.g. server rooms) e.g SY flex, or tuff sheathed

https://www.doncastercables.com/cables/5/10/Control-Cable/SY-Steel-Wire-Braid-Flexible-PVC-Control-Cable/


https://www.doncastercables.com/cables/6/24/SWA-and-Mains-Distribution/XLPE-Insulated--PVC-Bedded-and-Tuf-Sheathed-Non-Armoured-Cables/


And YY

https://www.doncastercables.com/cabl...Control-Cable/

--
Adam

In article , John J
wrote:
On Saturday, 6 February 2021 at 23:15:02 UTC, Theo wrote:
While I was on the TLC website I was doing a thought experiment.

Twin and earth cable comes in a variety of sizes: 1, 1.5, 2.5, 4, 6,
10, 16 mm2.

But what if you want to wire three phase? TLC only have 1 and 1.5mm2
three core and earth. Doncaster Cables also have 2.5mm2 but not
larger. CEF likewise. There's some three core in SWA but I assume
that's primarily for external use?

I understand that using three phase you can get 3x the power compared
to single phase - so a 32A radial would get you 7.3kW single phase or
22kW three phase.

But how should you wire that? For a 32A single phase radial the TLC
calculator indicates it needs 6mm2. What cable do you use for three
phase?

I suppose you could run a pair of 4/6/10mm2 T&E but that would seem
'surprising' - one of those pairs carries two phases instead of live
and neutral, and anyone who mixes up a phase for neutral may be in for
a shock. Plus the colour scheme is confusing (two brown and two blue,
which phase is which again? You can sleeve, but what if you mix up the
cables?)

You could use SWA, but that's fairly unwieldy and pricey for an
internal installation.

So what's the 'proper' way to do it?

Thanks Theo

You could go to a "proper" supplier but are you really planning to
install a three phase circuit in a domestic property or just shooting the
breeze?

does the premises have 3 phases incoming? If not, it might be quite pricey
to have your supply upgraded.

--
from KT24 in Surrey, England
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle

Which reminded me of something I'd not thought of for many years. For a
while you could get insulated wire which had small grooves in the sleeping
in various configurations. That would have been great today for
identification of which wire was which in dark areas or for us blindies. I
don't think its a thing any more, probably it compromised the strength of
the sleeving or something in which case they could have made it a tiny
tactile raised line instead?
Be ideal for the colour blind electrician!

Brian

--

This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"newshound" wrote in message
...
On 06/02/2021 23:14, Theo wrote:
While I was on the TLC website I was doing a thought experiment.

Twin and earth cable comes in a variety of sizes:
1, 1.5, 2.5, 4, 6, 10, 16 mm2.

But what if you want to wire three phase? TLC only have 1 and 1.5mm2
three
core and earth. Doncaster Cables also have 2.5mm2 but not larger. CEF
likewise. There's some three core in SWA but I assume that's primarily
for
external use?

I understand that using three phase you can get 3x the power compared to
single phase - so a 32A radial would get you 7.3kW single phase or 22kW
three phase.

But how should you wire that? For a 32A single phase radial the TLC
calculator indicates it needs 6mm2. What cable do you use for three
phase?

I suppose you could run a pair of 4/6/10mm2 T&E but that would seem
'surprising' - one of those pairs carries two phases instead of live and
neutral, and anyone who mixes up a phase for neutral may be in for a
shock.
Plus the colour scheme is confusing (two brown and two blue, which phase
is
which again? You can sleeve, but what if you mix up the cables?)

You could use SWA, but that's fairly unwieldy and pricey for an internal
installation.

So what's the 'proper' way to do it?

Thanks
Theo

IME at the domestic / light industrial level 3 phase is usually wired in
single core.

ARW wrote:
And YY

https://www.doncastercables.com/cabl...Control-Cable/

Interesting - is it common to use stranded rather than solid core?
I was looking for solid core which might have been why I didn't find these.

Theo

John J wrote:
You could go to a "proper" supplier but are you really planning to install
a three phase circuit in a domestic property or just shooting the breeze?

The train of thought was that, as part of current works, I'm thinking of
putting in a circuit for EV charging. I don't have an EV, nor do I have a
space on the CU to fit it, but working on the 'materials are cheap, labour
is expensive' principle (especially when you've made good on top of
everything) it's only the cost of the cable to do it now. The CU
replacement is likely to happen in the medium term (which would include
wiring in this cable), which just leaves the (relatively limited) external
wiring for the EVSE.

And then, scope creep being what it is, I was pondering what the uplift to
three phase would be. I don't have a three phase supply, but it's 'just'
another conductor to go from 6mm2 T&E to 6mm2 three core and earth. And
then we'd be all set for a three phase EV charger - for example, charging
multiple EVs at once. That would mean upgrading the supply, but longer term
we might have to move it anyway and the uplift in costs to the DNO from
single to three phase isn't *that* much.

But I couldn't find regular 'three core and earth' at suitable gauge, which
is why I was wondering...


Given that I don't seem to be able to buy the suggested cables in less than
100m lengths, is running a pair of T&E with suitable sleeving a Really
Really Bad idea? I suppose it doesn't matter until the point that 3 phase
comes into the equation (just a regular single phase circuit up to that
point), but if it came to that would it be up to code?

Until going 3 phase I could run the two T&E in parallel to reduce
losses/heating, but I suppose that might be 'surprising' - would it be
unacceptable?

Theo

On 07/02/2021 10:59, Theo wrote:
John J wrote:
You could go to a "proper" supplier but are you really planning to install
a three phase circuit in a domestic property or just shooting the breeze?

The train of thought was that, as part of current works, I'm thinking of
putting in a circuit for EV charging. I don't have an EV, nor do I have a
space on the CU to fit it, but working on the 'materials are cheap, labour
is expensive' principle (especially when you've made good on top of
everything) it's only the cost of the cable to do it now. The CU
replacement is likely to happen in the medium term (which would include
wiring in this cable), which just leaves the (relatively limited) external
wiring for the EVSE.

And then, scope creep being what it is, I was pondering what the uplift to
three phase would be. I don't have a three phase supply, but it's 'just'
another conductor to go from 6mm2 T&E to 6mm2 three core and earth. And
then we'd be all set for a three phase EV charger - for example, charging
multiple EVs at once. That would mean upgrading the supply, but longer term
we might have to move it anyway and the uplift in costs to the DNO from
single to three phase isn't *that* much.

But I couldn't find regular 'three core and earth' at suitable gauge, which
is why I was wondering...


Given that I don't seem to be able to buy the suggested cables in less than
100m lengths, is running a pair of T&E with suitable sleeving a Really
Really Bad idea? I suppose it doesn't matter until the point that 3 phase
comes into the equation (just a regular single phase circuit up to that
point), but if it came to that would it be up to code?

I would have thought that running single cores in insulated or steel
earthed conduit would be the normal way to go




--
There is nothing a fleet of dispatchable nuclear power plants cannot do
that cannot be done worse and more expensively and with higher carbon
emissions and more adverse environmental impact by adding intermittent
renewable energy.

Theo wrote:

The train of thought was that, as part of current works, I'm thinking of
putting in a circuit for EV charging. I don't have an EV, nor do I have a
space on the CU to fit it, but working on the 'materials are cheap, labour
is expensive' principle (especially when you've made good on top of
everything) it's only the cost of the cable to do it now. The CU
replacement is likely to happen in the medium term (which would include
wiring in this cable), which just leaves the (relatively limited) external
wiring for the EVSE.

And then, scope creep being what it is, I was pondering what the uplift to
three phase would be.

If you want maximum future proofing, put in cable that can handle
connection to one or more current transformers for "smart" charge points.

https://www.doncastercables.com/cables/17/77/EV-Ultra/Power-and-data-connectivity-combined-in-one-cable/

On 07/02/2021 10:59, Theo wrote:
John J wrote:
You could go to a "proper" supplier but are you really planning to install
a three phase circuit in a domestic property or just shooting the breeze?

The train of thought was that, as part of current works, I'm thinking of
putting in a circuit for EV charging. I don't have an EV, nor do I have a
space on the CU to fit it, but working on the 'materials are cheap, labour
is expensive' principle (especially when you've made good on top of
everything) it's only the cost of the cable to do it now. The CU
replacement is likely to happen in the medium term (which would include
wiring in this cable), which just leaves the (relatively limited) external
wiring for the EVSE.

And then, scope creep being what it is, I was pondering what the uplift to
three phase would be. I don't have a three phase supply, but it's 'just'
another conductor to go from 6mm2 T&E to 6mm2 three core and earth. And
then we'd be all set for a three phase EV charger - for example, charging
multiple EVs at once. That would mean upgrading the supply, but longer term
we might have to move it anyway and the uplift in costs to the DNO from
single to three phase isn't *that* much.

But I couldn't find regular 'three core and earth' at suitable gauge, which
is why I was wondering...


Given that I don't seem to be able to buy the suggested cables in less than
100m lengths, is running a pair of T&E with suitable sleeving a Really
Really Bad idea? I suppose it doesn't matter until the point that 3 phase
comes into the equation (just a regular single phase circuit up to that
point), but if it came to that would it be up to code?


TLC sell up to 6mm 3-core NYY-J by the meter

https://www.tlc-direct.co.uk/Products/NY6slash3.html


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

On 07/02/2021 10:59, Theo wrote:
John J wrote:
You could go to a "proper" supplier but are you really planning to install
a three phase circuit in a domestic property or just shooting the breeze?

The train of thought was that, as part of current works, I'm thinking of
putting in a circuit for EV charging. I don't have an EV, nor do I have a
space on the CU to fit it, but working on the 'materials are cheap, labour
is expensive' principle (especially when you've made good on top of
everything) it's only the cost of the cable to do it now. The CU
replacement is likely to happen in the medium term (which would include
wiring in this cable), which just leaves the (relatively limited) external
wiring for the EVSE.

And then, scope creep being what it is, I was pondering what the uplift to
three phase would be. I don't have a three phase supply, but it's 'just'
another conductor to go from 6mm2 T&E to 6mm2 three core and earth. And
then we'd be all set for a three phase EV charger - for example, charging
multiple EVs at once. That would mean upgrading the supply, but longer term
we might have to move it anyway and the uplift in costs to the DNO from
single to three phase isn't *that* much.

But I couldn't find regular 'three core and earth' at suitable gauge, which
is why I was wondering...

I believe 3PH chargers also need a neutral.



--
Adam

On 07/02/2021 11:27, Robin wrote:



TLC sell up to 6mm 3-core NYY-J by the meter

https://www.tlc-direct.co.uk/Products/NY6slash3.html



Yes but he also needs and earth and neutral:-)

--
Adam

On 07/02/2021 10:59, Theo wrote:
John J wrote:
You could go to a "proper" supplier but are you really planning to install
a three phase circuit in a domestic property or just shooting the breeze?

The train of thought was that, as part of current works, I'm thinking of
putting in a circuit for EV charging. I don't have an EV, nor do I have a
space on the CU to fit it, but working on the 'materials are cheap, labour
is expensive' principle (especially when you've made good on top of
everything) it's only the cost of the cable to do it now. The CU
replacement is likely to happen in the medium term (which would include
wiring in this cable), which just leaves the (relatively limited) external
wiring for the EVSE.

And then, scope creep being what it is, I was pondering what the uplift to
three phase would be. I don't have a three phase supply, but it's 'just'
another conductor to go from 6mm2 T&E to 6mm2 three core and earth. And
then we'd be all set for a three phase EV charger - for example, charging
multiple EVs at once. That would mean upgrading the supply, but longer term
we might have to move it anyway and the uplift in costs to the DNO from
single to three phase isn't *that* much.

But I couldn't find regular 'three core and earth' at suitable gauge, which
is why I was wondering...

That's simply because 3+e is made for two-way lighting

On 07/02/2021 12:36, ARW wrote:
On 07/02/2021 11:27, Robin wrote:



TLC sell up to 6mm 3-core NYY-J by the meter

https://www.tlc-direct.co.uk/Products/NY6slash3.html



Yes but he also needs and earth and neutral:-)


D'Oh!

(I'd thought "with the 18th an EV charger he might well need a local
earth rod anyway so..." but then went full prat.)

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

Andy Burns wrote:
If you want maximum future proofing, put in cable that can handle
connection to one or more current transformers for "smart" charge points.

https://www.doncastercables.com/cables/17/77/EV-Ultra/Power-and-data-connectivity-combined-in-one-cable/

I would go for the cat5e version, but that's for the external cable run (in
SWA). I would terminate the cat5e inside the house, not run it all the way
back to the CU.

But it's not suitable for 3 phase.

Theo

On 07/02/2021 09:04, Jeff Layman wrote:
On 06/02/2021 23:43, Steve Walker wrote:
On 06/02/2021 23:20, newshound wrote:
On 06/02/2021 23:14, Theo wrote:
While I was on the TLC website I was doing a thought experiment.

Twin and earth cable comes in a variety of sizes:
1, 1.5, 2.5, 4, 6, 10, 16 mm2.

But what if you want to wire three phase?Â* TLC only have 1 and 1.5mm2
three
core and earth.Â* Doncaster Cables also have 2.5mm2 but not larger.Â* CEF
likewise.Â* There's some three core in SWA but I assume that's
primarily for
external use?

I understand that using three phase you can get 3x the power
compared to
single phase - so a 32A radial would get you 7.3kW single phase or 22kW
three phase.

But how should you wire that?Â* For a 32A single phase radial the TLC
calculator indicates it needs 6mm2.Â* What cable do you use for three
phase?

I suppose you could run a pair of 4/6/10mm2 T&E but that would seem
'surprising' - one of those pairs carries two phases instead of live
and
neutral, and anyone who mixes up a phase for neutral may be in for a
shock.
Plus the colour scheme is confusing (two brown and two blue, which
phase is
which again?Â* You can sleeve, but what if you mix up the cables?)

You could use SWA, but that's fairly unwieldy and pricey for an
internal
installation.

So what's the 'proper' way to do it?

Thanks
Theo

IME at the domestic / light industrial level 3 phase is usually wired in
single core.

And for heavier industrial use, you could use something like:

https://www.vwcable.com/nyy-nyy-j-ny...h-power-cable/


Although the biggest I have seen myself (while testing a gas turbine
generator set) used singles - 3 pairs of 500mm2

Somewhat coincidentally, and further to the thread which I started last
week with the subject "At what low mains voltages do devices stop
working?", there have been two 500kVA generators running locally while
work was being done on a substation (I thought one was 300kVA as it was
smaller than the other, but was informed by a guy from SSE that both
were 500kVA). Both had 5 cables from them, four were yellow and seemed
to be about 25mm diameter, the other was yellow with a green stripe and
was somewhat less - maybe 20mm in diameter. A rather poor close-up photo
of connections made to the overhead line (440V?) is shown he
https://ibb.co/vBgFpj3
I think it is possible to just make out the colours, and assume the
other ends hidden in the generator are also colour coded. Does the earth
carry less current, or it it just there in case the neutral fails as a
temporary backup?

I guess those 25 mm cables have about 300 - 350mm^2 wire in them, and
are rated at 500 - 1000A.

Not far form me is a house with a Tesla parked in the drive. There is a
shoe-box sized wall charger unit with a cable about 20 - 25 mm diameter
going into it. I assume that's 3-phase.


Sounds more like a single phase charger. The chap near me who had a
new supply to the house, requiring the road to be dug up, has a charger
box on his house wall that looks to be about 2 to 3 foot high by 18
inches wide. I assumed he has had a 3phase supply connected to the house
from the other side of the road (which being a slight curve, has all
the street lamps).

On 07/02/2021 12:49, Robin wrote:
On 07/02/2021 12:36, ARW wrote:
On 07/02/2021 11:27, Robin wrote:



TLC sell up to 6mm 3-core NYY-J by the meter

https://www.tlc-direct.co.uk/Products/NY6slash3.html



Yes but he also needs and earth and neutral:-)


D'Oh!

(I'd thought "with the 18th an EV charger he might well need a local
earth rod anyway so..." but then went full prat.)


The single phase unit I fitted at a school had a local earth rod. I
still had to export the house earth to protect the cable and isolate it
inside the charger.

The neutral I believe had two purposes. One is to allow you to charge a
non three phase EV and the other is to provide 230V for the control
gear/interface on the charger.

--
Adam

On 07/02/2021 12:36, ARW wrote:
On 07/02/2021 11:27, Robin wrote:



TLC sell up to 6mm 3-core NYY-J by the meter

https://www.tlc-direct.co.uk/Products/NY6slash3.html



Yes but he also needs and earth and neutral:-)

you don't need a neutral with 3 ph surely?


--
Canada is all right really, though not for the whole weekend.

"Saki"

On 07/02/2021 11:14, Andy Burns wrote:
Theo wrote:

The train of thought was that, as part of current works, I'm thinking of
putting in a circuit for EV charging.Â* I don't have an EV, nor do I
have a
space on the CU to fit it, but working on the 'materials are cheap,
labour
is expensive' principle (especially when you've made good on top of
everything) it's only the cost of the cable to do it now.Â* The CU
replacement is likely to happen in the medium term (which would include
wiring in this cable), which just leaves the (relatively limited)
external
wiring for the EVSE.

And then, scope creep being what it is, I was pondering what the
uplift to
three phase would be.

If you want maximum future proofing, put in cable that can handle
connection to one or more current transformers for "smart" charge points.

https://www.doncastercables.com/cables/17/77/EV-Ultra/Power-and-data-connectivity-combined-in-one-cable/


But you might have to buy a minimum amount, like 25 metres


https://www.toolstation.com/cut-to-l...r-cable/p56272

On 07/02/2021 13:28, ARW wrote:
On 07/02/2021 12:49, Robin wrote:
On 07/02/2021 12:36, ARW wrote:
On 07/02/2021 11:27, Robin wrote:



TLC sell up to 6mm 3-core NYY-J by the meter

https://www.tlc-direct.co.uk/Products/NY6slash3.html



Yes but he also needs and earth and neutral:-)


D'Oh!

(I'd thought "with the 18th an EV charger he might well need a local
earth rod anyway so..." but then went full prat.)


The single phase unit I fitted at a school had a local earth rod. I
still had to export the house earth to protect the cable and isolate it
inside the charger.

The neutral I believe had two purposes. One is to allow you to charge a
non three phase EV and the other is to provide 230V for the control
gear/interface on the charger.


Does that mean you connected the SWA braid to the house earth (which
seems to make sense) ?. If so, what is the earth connector in the
cable connected to ?.

On Sunday, 7 February 2021 at 12:49:41 UTC, Robin wrote:
On 07/02/2021 12:36, ARW wrote:
On 07/02/2021 11:27, Robin wrote:



TLC sell up to 6mm 3-core NYY-J by the meter

https://www.tlc-direct.co.uk/Products/NY6slash3.html



Yes but he also needs and earth and neutral:-)

D'Oh!

(I'd thought "with the 18th an EV charger he might well need a local
earth rod anyway so..." but then went full prat.)
--
Robin
reply-to address is (intended to be) valid


Not according to this guy, bear in mind he was sponsored by the manufacturer for this video. Interesting all the same.

https://youtu.be/DnEG8jhOHBw

Richard

On 7 Feb 2021 at 13:29:39 GMT, "The Natural Philosopher"
wrote:

On 07/02/2021 12:36, ARW wrote:
On 07/02/2021 11:27, Robin wrote:



TLC sell up to 6mm 3-core NYY-J by the meter

https://www.tlc-direct.co.uk/Products/NY6slash3.html



Yes but he also needs and earth and neutral:-)

you don't need a neutral with 3 ph surely?

I think it depends on what you have connected to it. The second hand 1HP three
phase motor I obtained turned out only to have star wired connections so I did
need a neutral. In another post someone pointed out that if you need to use a
single phase for control circuits you also need neutral.


--
Roger Hayter

On 07/02/2021 13:39, Tricky Dicky wrote:
On Sunday, 7 February 2021 at 12:49:41 UTC, Robin wrote:
On 07/02/2021 12:36, ARW wrote:
On 07/02/2021 11:27, Robin wrote:



TLC sell up to 6mm 3-core NYY-J by the meter

https://www.tlc-direct.co.uk/Products/NY6slash3.html



Yes but he also needs and earth and neutral:-)

D'Oh!

(I'd thought "with the 18th an EV charger he might well need a local
earth rod anyway so..." but then went full prat.)
--
Robin
reply-to address is (intended to be) valid


Not according to this guy, bear in mind he was sponsored by the manufacturer for this video. Interesting all the same.

https://youtu.be/DnEG8jhOHBw



Zappis do not require an earth rod.


--
Adam

On 07/02/2021 13:35, Andrew wrote:
On 07/02/2021 13:28, ARW wrote:
On 07/02/2021 12:49, Robin wrote:
On 07/02/2021 12:36, ARW wrote:
On 07/02/2021 11:27, Robin wrote:



TLC sell up to 6mm 3-core NYY-J by the meter

https://www.tlc-direct.co.uk/Products/NY6slash3.html



Yes but he also needs and earth and neutral:-)


D'Oh!

(I'd thought "with the 18th an EV charger he might well need a local
earth rod anyway so..." but then went full prat.)


The single phase unit I fitted at a school had a local earth rod. I
still had to export the house earth to protect the cable and isolate
it inside the charger.

The neutral I believe had two purposes. One is to allow you to charge
a non three phase EV and the other is to provide 230V for the control
gear/interface on the charger.


Does that mean you connected the SWA braid to the house earth (which
seems to make sense) ?. If so, what is the earth connector in the
cable connected to ?.


Yes, SWA braid connected up at head end and at the charger end it went
into SWA gland inside a plastic box and no further. The charger had a
local earth rod.

--
Adam

In article ,
newshound wrote:
That's simply because 3+e is made for two-way lighting

Then it makes no sense to use three phase wiring colours.

--
*Consciousness: That annoying time between naps.

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

On 07/02/2021 13:28, ARW wrote:
On 07/02/2021 12:49, Robin wrote:
On 07/02/2021 12:36, ARW wrote:
On 07/02/2021 11:27, Robin wrote:



TLC sell up to 6mm 3-core NYY-J by the meter

https://www.tlc-direct.co.uk/Products/NY6slash3.html



Yes but he also needs and earth and neutral:-)


D'Oh!

(I'd thought "with the 18th an EV charger he might well need a local
earth rod anyway so..." but then went full prat.)


The single phase unit I fitted at a school had a local earth rod. I
still had to export the house earth to protect the cable and isolate it
inside the charger.


Would you have needed to export the earth if not using SWA - eg where
the cable ran inside a house, under the floor? (Purely academic question
for me in a terraced house with no off-street parking. Unless they
allow consumers to be inventive - eg a swing arm derrick across the
pavement.)




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

Robin wrote:
Would you have needed to export the earth if not using SWA - eg where
the cable ran inside a house, under the floor? (Purely academic question
for me in a terraced house with no off-street parking. Unless they
allow consumers to be inventive - eg a swing arm derrick across the
pavement.)

It depends on your EVSE, but the new fancypants ones don't need an earth rod
because they detect a current flowing from neutral to earth (in the case of
a broken PEN) and disconnect the supply. In that case the EVSE does need a
an earth from the supply to be able to detect that condition.

https://myenergi.com/pen-protection/

Theo

On 07/02/2021 14:17, Robin wrote:
On 07/02/2021 13:28, ARW wrote:
On 07/02/2021 12:49, Robin wrote:
On 07/02/2021 12:36, ARW wrote:
On 07/02/2021 11:27, Robin wrote:



TLC sell up to 6mm 3-core NYY-J by the meter

https://www.tlc-direct.co.uk/Products/NY6slash3.html



Yes but he also needs and earth and neutral:-)


D'Oh!

(I'd thought "with the 18th an EV charger he might well need a local
earth rod anyway so..." but then went full prat.)


The single phase unit I fitted at a school had a local earth rod. I
still had to export the house earth to protect the cable and isolate
it inside the charger.


Would you have needed to export the earth if not using SWA - eg where
the cable ran inside a house, under the floor? (Purely academic question
for me in a terraced house with no off-street parking.Â* Unless they
allow consumers to be inventive - eg a swing arm derrick across the
pavement.)





That is a good question as any short (lets assume you ran 4 core NYY-J
cable) would be LL or LN and thus trip the head end MCB. A totally
different thing to me using SWA.

I'll have to ask my contracts manager that one.

I suspect that you might not need to export and then isolate an earth.
After all if the car charging point was at the other side of the wall to
the CU I would not bother.



--
Adam

Roger Hayter wrote in
:


I think it depends on what you have connected to it. The second hand
1HP three phase motor I obtained turned out only to have star wired
connections so I did need a neutral. In another post someone pointed
out that if you need to use a single phase for control circuits you
also need neutral.

No need for a neutral in that config, the phase currents cancel at the star
giving no neutral shift.

ARW wrote:

I suspect that you might not need to export and then isolate an earth.
After all if the car charging point was at the other side of the wall to
the CU I would not bother.

All the examples I've seen have exported an earth on the armour of the
SWA, but then isolated it within the EV charger, so it's only there to
protect the cable, then use a rod to provide separate earth to the car.

It gets more involved if there's e.g. a bonded outside tap within reach
of the car, as they you could touch two different earths.

The zappi route is more expensive, but easier as it disconnects all
connections live/neutral/earth to the car if it senses a fault.

It's not just zappi now, there are others now which use the same method
for PEN fault detection ...

https://youtu.be/wCsTxj9aSLc?t=206

On 07/02/2021 14:12, Dave Plowman (News) wrote:
In article ,
newshound wrote:
That's simply because 3+e is made for two-way lighting

Then it makes no sense to use three phase wiring colours.



Well you cannot just use 3 browns can you?

--
Adam

Andrew wrote:
On 07/02/2021 09:04, Jeff Layman wrote:
On 06/02/2021 23:43, Steve Walker wrote:
On 06/02/2021 23:20, newshound wrote:
On 06/02/2021 23:14, Theo wrote:
While I was on the TLC website I was doing a thought experiment.

Twin and earth cable comes in a variety of sizes:
1, 1.5, 2.5, 4, 6, 10, 16 mm2.

But what if you want to wire three phase?Â* TLC only have 1 and 1.5mm2
three
core and earth.Â* Doncaster Cables also have 2.5mm2 but not larger.Â* CEF
likewise.Â* There's some three core in SWA but I assume that's
primarily for
external use?

I understand that using three phase you can get 3x the power
compared to
single phase - so a 32A radial would get you 7.3kW single phase or 22kW
three phase.

But how should you wire that?Â* For a 32A single phase radial the TLC
calculator indicates it needs 6mm2.Â* What cable do you use for three
phase?

I suppose you could run a pair of 4/6/10mm2 T&E but that would seem
'surprising' - one of those pairs carries two phases instead of live
and
neutral, and anyone who mixes up a phase for neutral may be in for a
shock.
Plus the colour scheme is confusing (two brown and two blue, which
phase is
which again?Â* You can sleeve, but what if you mix up the cables?)

You could use SWA, but that's fairly unwieldy and pricey for an
internal
installation.

So what's the 'proper' way to do it?

Thanks
Theo

IME at the domestic / light industrial level 3 phase is usually wired in
single core.

And for heavier industrial use, you could use something like:

https://www.vwcable.com/nyy-nyy-j-ny...h-power-cable/



Although the biggest I have seen myself (while testing a gas turbine
generator set) used singles - 3 pairs of 500mm2

Somewhat coincidentally, and further to the thread which I started last
week with the subject "At what low mains voltages do devices stop
working?", there have been two 500kVA generators running locally while
work was being done on a substation (I thought one was 300kVA as it was
smaller than the other, but was informed by a guy from SSE that both
were 500kVA). Both had 5 cables from them, four were yellow and seemed
to be about 25mm diameter, the other was yellow with a green stripe and
was somewhat less - maybe 20mm in diameter. A rather poor close-up photo
of connections made to the overhead line (440V?) is shown he
https://ibb.co/vBgFpj3
I think it is possible to just make out the colours, and assume the
other ends hidden in the generator are also colour coded. Does the earth
carry less current, or it it just there in case the neutral fails as a
temporary backup?

I guess those 25 mm cables have about 300 - 350mm^2 wire in them, and
are rated at 500 - 1000A.

Not far form me is a house with a Tesla parked in the drive. There is a
shoe-box sized wall charger unit with a cable about 20 - 25 mm diameter
going into it. I assume that's 3-phase.


Sounds more like a single phase charger. The chap near me who had a
new supply to the house, requiring the road to be dug up, has a charger
box on his house wall that looks to be about 2 to 3 foot high by 18
inches wide. I assumed he has had a 3phase supply connected to the house
from the other side of the road (which being a slight curve, has all
the street lamps).


The vast majority of domestic chargers will be single phase 7kW chargers.
Theres really no need for most folk to have three phase if they can charge
overnight and the cost of upgrading a domestic supply to 3 phase just
doesnt make it cost effective. Pointless unless you have a very specific
reason to need faster charging at home.

Tim

--
Please don't feed the trolls

On 07/02/2021 13:20, Andrew wrote:
On 07/02/2021 09:04, Jeff Layman wrote:
On 06/02/2021 23:43, Steve Walker wrote:
On 06/02/2021 23:20, newshound wrote:
On 06/02/2021 23:14, Theo wrote:
While I was on the TLC website I was doing a thought experiment.

Twin and earth cable comes in a variety of sizes:
1, 1.5, 2.5, 4, 6, 10, 16 mm2.

But what if you want to wire three phase?Â* TLC only have 1 and 1.5mm2
three
core and earth.Â* Doncaster Cables also have 2.5mm2 but not larger.Â* CEF
likewise.Â* There's some three core in SWA but I assume that's
primarily for
external use?

I understand that using three phase you can get 3x the power
compared to
single phase - so a 32A radial would get you 7.3kW single phase or 22kW
three phase.

But how should you wire that?Â* For a 32A single phase radial the TLC
calculator indicates it needs 6mm2.Â* What cable do you use for three
phase?

I suppose you could run a pair of 4/6/10mm2 T&E but that would seem
'surprising' - one of those pairs carries two phases instead of live
and
neutral, and anyone who mixes up a phase for neutral may be in for a
shock.
Plus the colour scheme is confusing (two brown and two blue, which
phase is
which again?Â* You can sleeve, but what if you mix up the cables?)

You could use SWA, but that's fairly unwieldy and pricey for an
internal
installation.

So what's the 'proper' way to do it?

Thanks
Theo

IME at the domestic / light industrial level 3 phase is usually wired in
single core.

And for heavier industrial use, you could use something like:

https://www.vwcable.com/nyy-nyy-j-ny...h-power-cable/


Although the biggest I have seen myself (while testing a gas turbine
generator set) used singles - 3 pairs of 500mm2

Somewhat coincidentally, and further to the thread which I started last
week with the subject "At what low mains voltages do devices stop
working?", there have been two 500kVA generators running locally while
work was being done on a substation (I thought one was 300kVA as it was
smaller than the other, but was informed by a guy from SSE that both
were 500kVA). Both had 5 cables from them, four were yellow and seemed
to be about 25mm diameter, the other was yellow with a green stripe and
was somewhat less - maybe 20mm in diameter. A rather poor close-up photo
of connections made to the overhead line (440V?) is shown he
https://ibb.co/vBgFpj3
I think it is possible to just make out the colours, and assume the
other ends hidden in the generator are also colour coded. Does the earth
carry less current, or it it just there in case the neutral fails as a
temporary backup?

I guess those 25 mm cables have about 300 - 350mm^2 wire in them, and
are rated at 500 - 1000A.

Not far form me is a house with a Tesla parked in the drive. There is a
shoe-box sized wall charger unit with a cable about 20 - 25 mm diameter
going into it. I assume that's 3-phase.


Sounds more like a single phase charger. The chap near me who had a
new supply to the house, requiring the road to be dug up, has a charger
box on his house wall that looks to be about 2 to 3 foot high by 18
inches wide. I assumed he has had a 3phase supply connected to the house
from the other side of the road (which being a slight curve, has all
the street lamps).

The box is this one:
https://www.smarthomecharge.co.uk/chargers/tesla/tesla-wall-connector/

That can be single or 3-phase. This is a new estate still being built.
The house in question was built three or four years ago, so could well
have a 3-phase supply.

--

Jeff

Andy Burns wrote:
The zappi route is more expensive, but easier as it disconnects all
connections live/neutral/earth to the car if it senses a fault.

It's not just zappi now, there are others now which use the same method
for PEN fault detection ...

This looks handy - provides the neutral/earth current detection and
disconnect for an existing charger:
https://www.cef.co.uk/catalogue/prod...rotection-unit

Theo

Tim+ wrote:
The vast majority of domestic chargers will be single phase 7kW chargers.
Theres really no need for most folk to have three phase if they can charge
overnight and the cost of upgrading a domestic supply to 3 phase just
doesnt make it cost effective. Pointless unless you have a very specific
reason to need faster charging at home.

There's more call for it if you have multiple EVs that you might want to
charge concurrently. For example families where the parents have two cars
and maybe the offspring living at home have a car or two. Or households of
multiple adults living in one house.

Theo

Theo wrote:

I understand that using three phase you can get 3x the power compared to
single phase - so a 32A radial would get you 7.3kW single phase or 22kW
three phase.

Is it 3 times, or is it sqrt(3) times ?

Andy Burns wrote in news:i8ar27Fr30pU1
@mid.individual.net:

Theo wrote:

I understand that using three phase you can get 3x the power compared to
single phase - so a 32A radial would get you 7.3kW single phase or 22kW
three phase.

Is it 3 times, or is it sqrt(3) times ?

3 times.

All the phases are carring 32A so that power has to go somewhere, it
doesn't matter if the currents cancel in middle.

If in doubt consider 3 x 32A loads to neutral 3 x power.