| Author |
Message |
Peter Bennett
Guest
|
 Posted:
Sun Feb 13, 2005 6:10 am Post subject:
Re: How much current safe for 30m extension? |
|
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On Sat, 12 Feb 2005 17:17:16 -0800, "Watson A.Name - \"Watt Sun, the
Dark Remover\"" <NOSPAM@dslextreme.com> wrote:
| Quote: | No. These cells are 4V each, 12 in all, each is sealed. Well, except
for the one cell that's split open because of internal pressure. :-(
They must be replaced, not repaired. This is a phone system, where it
has to be online during emergencies. Batteries that are working fine,
but over 5 years old are considered unacceptable and must be replaced.
|
I don't know of any 4 volt rechargeable cell chemistry.
I expect that your "4 volt cells" are actually two cell lead-acid
batteries, with each cell good for 2.1 volts.
--
Peter Bennett, VE7CEI
peterbb4 (at) interchange.ubc.ca
new newsgroup users info : http://vancouver-webpages.com/nnq
GPS and NMEA info: http://vancouver-webpages.com/peter
Vancouver Power Squadron: http://vancouver.powersquadron.ca
|
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Watson A.Name - \"Watt Su
Guest
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| Posted:
Sun Feb 13, 2005 6:10 am Post subject:
Re: How much current safe for 30m extension? |
|
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"John Rumm" <see.my.signature@nowhere.null> wrote in message
news:420e7d2d$0$29771$ed2619ec@ptn-nntp-reader02.plus.net...
| Quote: | ehsjr@bellatlantic.net wrote:
I think installing a half mile of # 4 might be "politically" cost
prohibitive, regardless of the technical merits. And I doubt
it would be a good financial solution. How many times
can you replace the batteries for the cost of digging a
1/4 mile trench, and installing conduit, cable, fittings,
transformers, etc ?
For that money you coud buy the PBX a UPS all of its very own!
|
That's probably what will happen. But the computer room's UPS is backed
up by a 300kW Caterpillar diesel generator, with 300 gallons of fuel in
the tank. It's supposed to run for at least 8 hours, so it does have an
advantage. We've had power outages that last for hours, so having that
much battery backup on the PBX would cost a lot more. But we'll
probably buy a couple APS 2.2kW UPses and put the PBX system on those.
They should last for close to an hour.
|
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Watson A.Name - \"Watt Su
Guest
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| Posted:
Sun Feb 13, 2005 6:10 am Post subject:
Re: How much current safe for 30m extension? |
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"Mike" <nospam@bt.com> wrote in message
news:cum1in$ci0$1@news6.svr.pol.co.uk...
| Quote: |
"Watson A.Name - "Watt Sun, the Dark Remover"" <NOSPAM@dslextreme.com
wrote
in message news:110sjq6kis36k05@corp.supernews.com...
And then when they get tired of doing that, they go out and buy a
weed
wacker with the gas engine.
One question to somebody presumably residing in the western colonies.
What's a "weed wacker"?
|
Where are you from? Ever heard of Google?
This URL shows a pic of the business end of a weed wacker.
Traditionally they use monofilament. There are both electric and gas
engine types, but the noisy gasoline engines (and leaf blowers) are
sometimes banned from some communities.
http://www.nycgovparks.org/sub_newsroom/innovations/ino_06_2000.pdf
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Watson A.Name - \"Watt Su
Guest
|
| Posted:
Sun Feb 13, 2005 6:10 am Post subject:
Re: How much current safe for 30m extension? |
|
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"raden" <raden@kateda.org> wrote in message
news:Iv0Z3IeHyqDCFwIg@ntlworld.com...
| Quote: | In message <110taejtbujdh40@corp.supernews.com>, "Watson A.Name -
\"Watt
Sun, the Dark Remover\"" <NOSPAM@dslextreme.com> writes
T&E's probably far more practical.
Thanks, but I've never heard of T&E here in the U.S. I don't know
what
that acronym stands for.
Twin and earth
... colonials !
|
Yeah, we call it ground here stateside. And it's Romex.
And it's AC line in every schematic I've seen from the American mfgrs
the likes of HP, Tek, etc., not "mains". Mains are those wires up on
top of the power pole.
Thanks T.A.!!
(That's Thomas Alva, for you right ponders.) |
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Watson A.Name - \"Watt Su
Guest
|
| Posted:
Sun Feb 13, 2005 6:10 am Post subject:
Re: How much current safe for 30m extension? |
|
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"Peter Bennett" <peterbb@somewhere.invalid> wrote in message
news:42jt01h7q5dpasoeufg6gfa0d7mu1qmkcl@news.supernews.com...
| Quote: | On Sat, 12 Feb 2005 17:17:16 -0800, "Watson A.Name - \"Watt Sun, the
Dark Remover\"" <NOSPAM@dslextreme.com> wrote:
No. These cells are 4V each, 12 in all, each is sealed. Well,
except
for the one cell that's split open because of internal pressure. :-(
They must be replaced, not repaired. This is a phone system, where
it
has to be online during emergencies. Batteries that are working
fine,
but over 5 years old are considered unacceptable and must be
replaced.
I don't know of any 4 volt rechargeable cell chemistry.
I expect that your "4 volt cells" are actually two cell lead-acid
batteries, with each cell good for 2.1 volts.
|
I expect you're right. Two cells in a case.
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Watson A.Name - \"Watt Su
Guest
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| Posted:
Sun Feb 13, 2005 6:10 am Post subject:
Re: How much current safe for 30m extension? |
|
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"Peter A Forbes" <diesel@easynet.co.uk> wrote in message
news:rpks01dusj3e57g4n976ii30l4ncc1stpj@4ax.com...
| Quote: | On Sat, 12 Feb 2005 10:51:00 -0800, "Watson A.Name - \"Watt Sun, the
Dark
Remover\"" <NOSPAM@dslextreme.com> wrote:
"Bob Eager" <rde42@spamcop.net> wrote in message
news:176uZD2KcidF-pn2-pgQf8dbMMKeL@rikki.tavi.co.uk...
On Sat, 12 Feb 2005 12:46:19 UTC, Ian Stirling
root@mauve.demon.co.uk
wrote:
Or for 60m, 8.4*10^-1 ohms, or .84 ohms.
Plus the resistance on the two connections. Not sure whether the
earth
fault loop impedance is still OK...
Yeah, true. You 220VAC and 240VAC guys think you got it bad, we have
four times as much of a problem here in 120VAC land. ;-)
Those poor souls that put a hundred feet or so of 18GA (about 1mm sq)
extension cord on their weed wackers soon find that not only does it
run
slow, but the motor overheats. So we have extension cords that are
16
or 14 gauge, and can handle the extra current. But people are too
cheap
to pay double for the heavy duty extension cord, so they end up
eating
their money up in burned out motors.
And then when they get tired of doing that, they go out and buy a
weed
wacker with the gas engine. This is on the end of a long pole, so
the
engine is right up next to their face, so they go deaf from all the
engine noise. And they put the weed wacker in the garage, where the
gas
from the tank runs out and catches on fire!
--
Bob Eager
Why use anything as small as 1mm sq cable???
For 30metres I'd want to see 2.5mm sq at least, if not 4mm sq.
If not for the volt drop or lack of, for the mechanical strength and
resistance
to damage.
|
Hey, a hedge trimmer will cut the cable cleanly in half, no matter what
size it is! Ask one of the ladies at work, she has first-hand
experience!
As for heavier cable, I know that, but the average consumer doesn't.
She uses an 18 gauge extension cord with the cast plastic socket from
the wall to her ironing board, and wonders why she smells melted plastic
when she irons! "Gee, I swear that when I plugged it in, the socket
wasn't all brown and charred." Doh!
The guy has what's at hand and just plugs three 25 footers together to
wack his weeds. The plugs and sockets also drop some voltage because of
their resistance, so he ends up with a burned out motor after it ran a
couple hours at 85 to 90VAC. Doh.
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Watson A.Name - \"Watt Su
Guest
|
| Posted:
Sun Feb 13, 2005 6:10 am Post subject:
Re: How much current safe for 30m extension? |
|
|
<bigcat@meeow.co.uk> wrote in message
news:1108237955.923021.112840@f14g2000cwb.googlegroups.com...
Watson A.Name - "Watt Sun, the Dark Remover" wrote:
| Quote: | "Sammo" <noone@no-where.com> wrote in message
news:95FB7BA1F25441A7D4@130.133.1.4...
I am in the UK (so mains voltage is about 230V or 240V).
I'm in the U.S. and this gives me a flashback on what I was thinking
about trying a few months ago. We have a PBX at work that's on 48V
batteries, but the batteries are 9 yrs old and need replacing. They
cost a bundle
the first logical thought is repair them rather than replace. Lead
acids are often repairable.
Quick repair, doesnt always work:
rinse muck out of cells
fill with new acid
charge, monitor acid conc and adjust as required
This wont fix all cells by any means, but many it will. Those it wont
in some cases may only need replacement plates and acid, which can be
made much cheaper than buying new batts.
|
No. These cells are 4V each, 12 in all, each is sealed. Well, except
for the one cell that's split open because of internal pressure. :-(
They must be replaced, not repaired. This is a phone system, where it
has to be online during emergencies. Batteries that are working fine,
but over 5 years old are considered unacceptable and must be replaced.
| Quote: | Also they can often be run happily at 24v, if not in all cases. If
yours could, it may be that your present cells would do that as is.
|
This is *not* how you run a battery backup system! The idea is to start
out with fully charged batteries, so that when the power fails for a
long period, the voltage of the batteries may drop to 40V or less as the
cells discharge, keeping the PBX online. If you start at anything less,
even 36V, you're not going to have any discharge time before the PBX
system crashes. It would be essentially worthless.
| Quote: | What capacity at 48v is it on?
|
The rectifier can put out a hundred amps at 54VDC, to charge the
batteries while the PBX is also running. That must be 6 or so kW input.
So I would guess that it's 208V at 30A breakers. But with no batteries,
the load would be more like 3.6kW.
| Quote: | I thought it would be possible to run a power cable
underground to the big UPS we have in our computer room. Problem is
that the PBX's rectifier takes 30A max at 120VAC, or about 3.6kW.
i've no ida how that fits into this
|
The UPS in the computer room is 150kW, easily capable of handling
another 6 or so kW.
| Quote: | And
the distance between is about 1300 feet or about 400m.
I would guess that the UPS output should go into a transformer and
come
out 480VAC, so the cable losses would be minimized. Then another
transf
on the PBX end to bring it back to 120VAC. But should I expect to
have
a max loss of 5% at max current, or what?
well how much current are you shifting??
And why cant you power your pbx from whatever power source it uses
now?
You havent given us nearly enough information.
|
The batteries and rectifier are a "UPS" to protect the PBX against
failure of the commercial power. That's what it's being fed from.
| Quote: | I think I came up with 4GA
cable, but at 480VAC, I'm guessing that it would have to be special
insulated underground cable.
standard uk T&E should do that, but shuold be insulation tested to the
required v first. Costs around £12 a 100m reel, depending on copper
size.
|
Assuming that it could be pulled 1300 feet. Probably not without
damage. Heavily insulated cable would be needed. Probably double
jacketed.
| Quote: | Someday I'll have to ask one of the electricians that work on our HV
stuff. We have 4160VAC underground around campus but that's all
specialized switchgear, etc.
rf transmission co-ax is rated pretty high... and its concentric.
|
RF transmission coax is typically copper clad steel wire center
conductor, which would have much greater I^2R loss than pure copper
cable at 50 or 60Hz. That would be unacceptable.
| Quote: | T&E's probably far more practical.
|
Thanks, but I've never heard of T&E here in the U.S. I don't know what
that acronym stands for.
[snip]
NT |
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raden
Guest
|
| Posted:
Sun Feb 13, 2005 6:10 am Post subject:
Re: How much current safe for 30m extension? |
|
|
In message <110taejtbujdh40@corp.supernews.com>, "Watson A.Name - \"Watt
Sun, the Dark Remover\"" <NOSPAM@dslextreme.com> writes
| Quote: |
T&E's probably far more practical.
Thanks, but I've never heard of T&E here in the U.S. I don't know what
that acronym stands for.
Twin and earth |
.... colonials !
--
geoff |
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Watson A.Name - \"Watt Su
Guest
|
| Posted:
Sun Feb 13, 2005 6:10 am Post subject:
Re: How much current safe for 30m extension? |
|
|
<ehsjr@bellatlantic.net> wrote in message
news:REtPd.19619$ya6.6306@trndny01...
| Quote: | Watson A.Name - "Watt Sun, the Dark Remover" wrote:
"Sammo" <noone@no-where.com> wrote in message
news:95FB7BA1F25441A7D4@130.133.1.4...
I am in the UK (so mains voltage is about 230V or 240V).
I'm in the U.S. and this gives me a flashback on what I was thinking
about trying a few months ago. We have a PBX at work that's on 48V
batteries, but the batteries are 9 yrs old and need replacing. They
cost a bundle so I thought it would be possible to run a power cable
underground to the big UPS we have in our computer room. Problem is
that the PBX's rectifier takes 30A max at 120VAC, or about 3.6kW.
And
the distance between is about 1300 feet or about 400m.
I would guess that the UPS output should go into a transformer and
come
out 480VAC, so the cable losses would be minimized. Then another
transf
on the PBX end to bring it back to 120VAC.
Hmmm... if you do it, just connect the PBX directly to the
480 volts. Just think how much faster the phone calls will
be at 480 vs 48! :-)
I think installing a half mile of # 4 might be "politically" cost
prohibitive, regardless of the technical merits. And I doubt
it would be a good financial solution. How many times
can you replace the batteries for the cost of digging a
1/4 mile trench, and installing conduit, cable, fittings,
transformers, etc ?
|
Last time we had a major failure of the batteries and rectifier it cost
over $15,000 to get it repaired. Obviously that was before 1996, when
the present batteries were installed. So the price would be somewhat
higher today.
The spare conduit is already in place underground, all that is needed
are the power cable and associated switchgear.
We regularly have the 4160VAC cabling HiPot tested on campus, and on
occasion a section has to be replaced. Y'ever see this stuff? It's
600MCM, with heavy insulation and shielding. The copper is as big as
your thumb, and it's expensive!! I have a footlong section of it on my
desk, and when someone asks what it is, I tell them it's high speed
datacomm cable! ;-) WOW! Really??
I googled for that and this URL says that 600MCM is 29mm. Fat pipe!
Imagine all the data you could shove thru it!
http://www.appatech.com/a-30.htm
[snip] |
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John Rumm
Guest
|
| Posted:
Sun Feb 13, 2005 6:10 am Post subject:
Re: How much current safe for 30m extension? |
|
|
Mike wrote:
| Quote: | One question to somebody presumably residing in the western colonies.
What's a "weed wacker" ?
|
"Strimmer" to us.
--
Cheers,
John.
/=================================================================\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\=================================================================/ |
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Tim (Remove NOSPAM.
Guest
|
| Posted:
Sun Feb 13, 2005 10:04 am Post subject:
Re: How much current safe for 30m extension? |
|
|
"Watson A.Name - "Watt Sun, the Dark Remover"" <NOSPAM@dslextreme.com> wrote
in message news:110teqojps8vsd1@corp.supernews.com...
| Quote: |
"Mike" <nospam@bt.com> wrote in message
news:cum1in$ci0$1@news6.svr.pol.co.uk...
"Watson A.Name - "Watt Sun, the Dark Remover"" <NOSPAM@dslextreme.com
wrote
in message news:110sjq6kis36k05@corp.supernews.com...
And then when they get tired of doing that, they go out and buy a
weed
wacker with the gas engine.
One question to somebody presumably residing in the western colonies.
What's a "weed wacker"?
Where are you from? Ever heard of Google?
This URL shows a pic of the business end of a weed wacker.
Traditionally they use monofilament. There are both electric and gas
engine types, but the noisy gasoline engines (and leaf blowers) are
sometimes banned from some communities.
|
Hell, if you have any more grass than that the size of a postage stamp here
in the UK, we buy a petrol driven "weed wacker", the electric ones, even at
230v are worse than useless!
Tim.. |
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Dave Plowman (News)
Guest
|
| Posted:
Sun Feb 13, 2005 12:13 pm Post subject:
Re: How much current safe for 30m extension? |
|
|
In article <rpks01dusj3e57g4n976ii30l4ncc1stpj@4ax.com>,
Peter A Forbes <diesel@easynet.co.uk> wrote:
| Quote: | Why use anything as small as 1mm sq cable???
For 30metres I'd want to see 2.5mm sq at least, if not 4mm sq.
If not for the volt drop or lack of, for the mechanical strength and
resistance to damage.
|
Dunno where you'd get 4mm flex, but you'd never get it to fit a 13 amp
plug. 2.5mm is the limit, and not all plugs will have a cord grip suitable.
--
*If a thing is worth doing, wouldn't it have been done already?
Dave Plowman dave@davenoise.co.uk London SW
To e-mail, change noise into sound. |
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Jerry G.
Guest
|
| Posted:
Sun Feb 13, 2005 12:25 pm Post subject:
Re: How much current safe for 30m extension? |
|
|
As long as the maximum current load does not exceed the current rating of
any of the cables that are used in the extension, it will be safe. There
should not be very much loss over a few hundred feet of extension. If there
is a loss, you can then change the extensions for ones that are of a larger
gauge.
I have run extensions of up to 400 feet. These were 10 Amp rated. I had no
performance loss in the loads that I was using. The load was about 4 to 5
amps. I am working with 120 VAC at my location. I took a voltage reading, at
the outlet, and one across the load. There was a drop of about one or two
volts. But, the total voltage at the extension output was still in specs
while under the load. The source voltage at the outlet was about 118 VAC.
Across the load, if I remember correctly, it was about approximately 116
VAC.
In areas that are using 220 VAC, the current is about 1/2 for the same
wattage, as when compared to 120 VAC. This would lead to less loss when
using an extension cord.
Most devices here in North America are rated at 105 to 125 VAC. Some are
rated from about 105 to 135 VAC.
--
Jerry G.
======
"Ian Stirling" <root@mauve.demon.co.uk> wrote in message
news:420dfa9a$0$45677$ed2e19e4@ptn-nntp-reader04.plus.net...
In uk.d-i-y Sammo <noone@no-where.com> wrote:
| Quote: | I am in the UK (so mains voltage is about 230V or 240V).
I have a reel of main extension cable made of 3-core 1.0 mm^2 wire
rated at 10 Amps. So the nominal power rating would be about 2,400
Watts. (Link to tech reference for the cable is below.)
|
It's always going to be safe, as it's got a fuse.
Ok...
Copper has a resistivity of 0.7*10^-8 ohms/meter.
Or, for a 1mm^2 wire, 0.7*10^-2 ohms/meter.
Or for 2 wires, 1.4*10^-2 ohms.
Or for 60m, 8.4*10^-1 ohms, or .84 ohms.
At 10A, 8.4V, or heating by 84W.
If at the plug end is 240V, at the socket end will be 232V, which is
(232^2/240^2)= .93444444444444444444
So, you lose 7% of the power for a heater, for example. |
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Dave Plowman (News)
Guest
|
| Posted:
Sun Feb 13, 2005 5:18 pm Post subject:
Re: How much current safe for 30m extension? |
|
|
In article <420f812d$0$8751$db0fefd9@news.zen.co.uk>,
Andy Wade <spambucket@ajwade.clara.co.uk> wrote:
| Quote: | Dunno where you'd get 4mm flex,
RS for one, see stock no. 250-1410.
but you'd never get it to fit a 13 amp plug. 2.5mm is the limit, and
not all plugs will have a cord grip suitable.
Actually 1.25 mm^2 is the limit - in the sense that it's the largest
size that BS 1363 requires a plug to accept. Nevertheless _most_ plugs
will accept 1.5 mm^2 without too much difficulty and _some_ will accept
2.5 mm^2.
|
Right. Didn't know chapter and verse.
Our location sparks use 2.5mm TRS for most uses - and as many things may
have to plug into a house supply at some point, use 13 amp adaptor leads
to feed theirs. Think the 13 amp plugs they use are Duraplugs
--
*A chicken crossing the road is poultry in motion.*
Dave Plowman dave@davenoise.co.uk London SW
To e-mail, change noise into sound. |
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Guest
|
| Posted:
Sun Feb 13, 2005 7:45 pm Post subject:
Re: How much current safe for 30m extension? |
|
|
Watson A.Name - "Watt Sun, the Dark Remover" wrote:
| Quote: | bigcat@meeow.co.uk> wrote in message
news:1108237955.923021.112840@f14g2000cwb.googlegroups.com...
I'm in the U.S. and this gives me a flashback on what I was
thinking
about trying a few months ago. We have a PBX at work that's on 48V
batteries, but the batteries are 9 yrs old and need replacing.
They
cost a bundle
the first logical thought is repair them rather than replace. Lead
acids are often repairable.
Quick repair, doesnt always work:
rinse muck out of cells
fill with new acid
charge, monitor acid conc and adjust as required
This wont fix all cells by any means, but many it will. Those it
wont
in some cases may only need replacement plates and acid, which can
be
made much cheaper than buying new batts.
No. These cells are 4V each, 12 in all, each is sealed.
|
If youre going to deal with this you'll need a few clues. You will have
2v cells in pairs, 4v lead acid cells dont exist.
| Quote: | Well, except
for the one cell that's split open because of internal pressure. :-(
They must be replaced, not repaired. This is a phone system, where
it
has to be online during emergencies. Batteries that are working
fine,
but over 5 years old are considered unacceptable and must be
replaced. |
thats fine if youve got the money, but since they've been there 9
years, and are found dead but still in service, I was guessing you
havent.
Is it April yet?
| Quote: | Also they can often be run happily at 24v, if not in all cases. If
yours could, it may be that your present cells would do that as is.
This is *not* how you run a battery backup system! The idea is to
start
out with fully charged batteries, so that when the power fails for a
long period, the voltage of the batteries may drop to 40V or less as
the
cells discharge, keeping the PBX online. If you start at anything
less,
even 36V, you're not going to have any discharge time before the PBX
system crashes. It would be essentially worthless.
|
You misunderstood completely, hopelessly, and idiotically. 48v is a
very old standard, and many 48v telecomms systems are now run on 24v.
If your equipment were 24v compatible, as some is, you would only need
half the number of cells.
And if you had no money to replace the battery, odds are you'll have at
least 50% of cells still serviceable.
Even if its not 24v compatible, you would get better backup performance
by removing any dead cells from the chain. Whether you remove them or
not you'll run below voltage.
| Quote: | What capacity at 48v is it on?
The rectifier can put out a hundred amps at 54VDC, to charge the
batteries while the PBX is also running. That must be 6 or so kW
input.
So I would guess that it's 208V at 30A breakers. But with no
batteries,
the load would be more like 3.6kW.
|
3.6kW @ 50v = 72A, so if we take an ultra-vague guess at C/10 charging,
that gives us 700ah capacity @48v. Ouch.
| Quote: | I thought it would be possible to run a power cable
underground to the big UPS we have in our computer room. Problem
is
that the PBX's rectifier takes 30A max at 120VAC, or about 3.6kW.
i've no ida how that fits into this
The UPS in the computer room is 150kW, easily capable of handling
another 6 or so kW.
And
the distance between is about 1300 feet or about 400m.
I would guess that the UPS output should go into a transformer and
come
out 480VAC, so the cable losses would be minimized. Then another
transf
on the PBX end to bring it back to 120VAC. But should I expect to
have
a max loss of 5% at max current, or what?
well how much current are you shifting??
And why cant you power your pbx from whatever power source it uses
now?
You havent given us nearly enough information.
The batteries and rectifier are a "UPS" to protect the PBX against
failure of the commercial power. That's what it's being fed from.
|
Why dont you find someone else to discuss this with.
| Quote: | I think I came up with 4GA
cable, but at 480VAC, I'm guessing that it would have to be special
insulated underground cable.
standard uk T&E should do that, but shuold be insulation tested to
the
required v first. Costs around £12 a 100m reel, depending on
copper
size.
Assuming that it could be pulled 1300 feet. Probably not without
damage.
|
You thread it section by section. Regular access points also allow a
section can be replaced if it fails. The T&E also includes a spare
conductor for backup.
| Quote: | Heavily insulated cable would be needed. Probably double
jacketed.
|
T&E is double insulated, high v rated and cheap - thats why i suggested
it.
| Quote: | Someday I'll have to ask one of the electricians that work on our
HV
stuff. We have 4160VAC underground around campus but that's all
specialized switchgear, etc.
rf transmission co-ax is rated pretty high... and its concentric.
RF transmission coax is typically copper clad steel wire center
conductor, which would have much greater I^2R loss than pure copper
cable at 50 or 60Hz. That would be unacceptable.
|
obviously it depends what v and i youre running it at, its very much
higher v rated than T&E.
| Quote: | T&E's probably far more practical.
Thanks, but I've never heard of T&E here in the U.S. I don't know
what
that acronym stands for.
|
twin and earth, its our standard house wiring cable, 2 cores double
insulated plus one single, comes in various copper sizes, is very cheap
and can be bought at thousands of outlets... here, anyway. I dont know
what export would cost.
You would need to get some basic concepts sorted out before youre in a
position to imlpement anything.
NT |
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