Well, the time has finally come to shift most of the computers out into
the garage (apparently).
Having already got enough power out there I need to put in a fat data
pipe to connect the lot to the house switch - cat5e will do nicely
because I have lots. Wireless is an absolute worst case scenario both
for speed and price and we need to connect to the servers for data
(video/music etc).

The garage is not connected to the house and is separated by about 3m of
paving/drive/whatnot.

Any suggestions for running the cable ?
I'm aware that pushing it through the same conduit as the power is a
no-go and I really don't want to dig up the drive unless I have to. I
suppose I could take it under a patio and through some of the lawn if I
must. On top of that I naturally don't want to spend very much time or
effort.

Chips.

--
-----------
Chips'll make it better.
-----------

The message
from Chips contains these words:

Any suggestions for running the cable ?

Anything wrong with wireless?

--
Skipweasel
Pay no attention to that man behind the curtain.

Guy King wrote:
The message
from Chips contains these words:

Any suggestions for running the cable ?

Anything wrong with wireless?


Other than the OP says he doesn't want it - worst case (cost / bandwidth).

....

on the other hand, I can stream 720p HD to the XBox-360 on 802.11g

Chips wrote :

The garage is not connected to the house and is separated by about 3m of
paving/drive/whatnot.

Any suggestions for running the cable ?



Catenary wire supporting a length of 20mm plastic conduit?

--

Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

The message
from Mike Dodd contains these words:

Any suggestions for running the cable ?

Anything wrong with wireless?


Other than the OP says he doesn't want it - worst case (cost / bandwidth).

Well, it's not /that/ expensive, and some systems do vast bandwidths
these days.

--
Skipweasel
Pay no attention to that man behind the curtain.

"Chips" wrote...
Well, the time has finally come to shift most of the computers out into
the garage (apparently).
Having already got enough power out there I need to put in a fat data pipe
to connect the lot to the house switch - cat5e will do nicely because I
have lots. Wireless is an absolute worst case scenario both for speed and
price and we need to connect to the servers for data (video/music etc).

The garage is not connected to the house and is separated by about 3m of
paving/drive/whatnot.

Any suggestions for running the cable ?
I'm aware that pushing it through the same conduit as the power is a no-go
and I really don't want to dig up the drive unless I have to. I suppose I
could take it under a patio and through some of the lawn if I must. On top
of that I naturally don't want to spend very much time or effort.

How about a pair of fibre media convertors and a short run of multimode
fibre in the conduit with the power? Even figure-8 patch cord will do for
this short a distance.

You get:
1) Noise immunity as the power won't interfere with the light;
2) Electrical isolation;
3) Lightning protection;
4) A Very Cool Thing to brag about ;o)

They're available in 10M, 100M and 1Gbit versions, depending on how fat a
pipe you want... prices depend on whether you scour Ebay/IT surplus outlets
etc. or buy new (ouch!), but start around £25 each if you're lucky.

BTW, cat5e cable isn't specified for immersion or wet environments, and
can/will be permeable to groundwater, resulting in Horrible Corrosion and
Degradation and eventual loss of its signal-carrying abilities, so don't
bury it (

Dave H.
(The engineer formerly known as Homeless)
(...who has a pair of fibre-connected Ethernet switches to get to his
garage - geek, eh?)

I know that Comms wiring practise does not recc. for running copper
comms between buildings due to risk of electrical faults, lightning
strikes etc.
The approved way is fibre (as mentioned)

Why not use WiFi 802.11g will give you 54Mbs or up top 100 Mb if you
use HSM compatible devices.


or go nuts and use pre-N

There is a mail order company called Tait Components who do external
cat5 or you could use 2x dlink wireless bridges DWL-2000AP+ with a
couple of external arials. using the fibre with dlink fibre media
converters would also work. Running the fibre, might find it difficult
getting through the conduit where your power cable is.

"Chips" wrote in message
...
Well, the time has finally come to shift most of the computers out into
the garage (apparently).
Having already got enough power out there I need to put in a fat data pipe
to connect the lot to the house switch - cat5e will do nicely because I
have lots. Wireless is an absolute worst case scenario both for speed and
price and we need to connect to the servers for data (video/music etc).

The garage is not connected to the house and is separated by about 3m of
paving/drive/whatnot.

Any suggestions for running the cable ?
I'm aware that pushing it through the same conduit as the power is a no-go
and I really don't want to dig up the drive unless I have to. I suppose I
could take it under a patio and through some of the lawn if I must. On top
of that I naturally don't want to spend very much time or effort.

My solution to running telephone, data and an air line between two
buildings a couple of metres apart was a piece of 100mm square 6mm wall
steel tube 3m above ground.

Colin Bignell

"Chips" wrote in message
...

snip

If you don't want wireless, then fibre is definately the way to go. If
100Mb/s would hack it, then a couple of D-link or ATI media converters
shouldn't cost too much.

If space in the conduit is a problem, make sure you use use fibe with
ST connectors these are only about 1/4" diameter and you can always
split the figure of eight "cable" so that you can feed them through
individualy. if push comes to shove, you could probably isolate,
disconnect and remove the mains, pull the fibre in and then pull the
mains back in.

Check the fibre is ok first!!

The message
from "nightjar" nightjar@insert my surname here.uk.com contains
these words:

My solution to running telephone, data and an air line between two
buildings a couple of metres apart was a piece of 100mm square 6mm wall
steel tube 3m above ground.

Don't you thing 1/4" thick walls was a bit OTT? To span a couple of
meters a bit of plastic drain pipe would have been fine.

--
Skipweasel
Pay no attention to that man behind the curtain.

Chips wrote:
Well, the time has finally come to shift most of the computers out into
the garage (apparently).
Having already got enough power out there I need to put in a fat data
pipe to connect the lot to the house switch - cat5e will do nicely
because I have lots. Wireless is an absolute worst case scenario both
for speed and price and we need to connect to the servers for data
(video/music etc).

The garage is not connected to the house and is separated by about 3m of
paving/drive/whatnot.

Any suggestions for running the cable ?
I'm aware that pushing it through the same conduit as the power is a
no-go and I really don't want to dig up the drive unless I have to. I
suppose I could take it under a patio and through some of the lawn if I
must. On top of that I naturally don't want to spend very much time or
effort.

Chips.

--
-----------
Chips'll make it better.
-----------

Stick your cat5e in the conduit with the power - you won't get any
problems. In industry, it's rarely possible to get any separation of
the two - I've never had a problem.

wrote:
Phil wrote:

Chips wrote:
Well, the time has finally come to shift most of the computers out into
the garage (apparently).
Having already got enough power out there I need to put in a fat data
pipe to connect the lot to the house switch - cat5e will do nicely
because I have lots. Wireless is an absolute worst case scenario both
for speed and price and we need to connect to the servers for data
(video/music etc).

The garage is not connected to the house and is separated by about 3m of
paving/drive/whatnot.

Any suggestions for running the cable ?
I'm aware that pushing it through the same conduit as the power is a
no-go and I really don't want to dig up the drive unless I have to. I
suppose I could take it under a patio and through some of the lawn if I
must. On top of that I naturally don't want to spend very much time or
effort.

Chips.

--
-----------
Chips'll make it better.
-----------

Stick your cat5e in the conduit with the power - you won't get any
problems. In industry, it's rarely possible to get any separation of
the two - I've never had a problem.

It won't conform to the IEE wiring regulations though, they require
either 50mm separation or 'physical' separation which seems to mean in
practice a divider in the conduit/trunking.

I agree that it will almost certainly work perfectly well.

--
Chris Green

So? The IEE won't be inspecting it.
Presumably the power installation has already been passed.

On 2006-05-22, Dave H. wrote:

"Chips" wrote...
Well, the time has finally come to shift most of the computers out into
the garage (apparently).
Having already got enough power out there I need to put in a fat data pipe
to connect the lot to the house switch - cat5e will do nicely because I
have lots. Wireless is an absolute worst case scenario both for speed and
price and we need to connect to the servers for data (video/music etc).

.......

How about a pair of fibre media convertors and a short run of multimode
fibre in the conduit with the power? Even figure-8 patch cord will do for
this short a distance.

.......

Whatever you end up doing (personally I'd go with an optical solution),
I would suggest you run some redundant circuits, either down the same conduit
or in a parallel channel. It's easier to do this now all in one go than to
have to start digging up the garden if you get a failure in the future.

Oh yes, don't forget to label the corresponding ends with a permanent
marker :-)

Pete
--
.................................................. .........................
.. never trust a man who, when left alone ...... Pete Lynch .
.. in a room with a tea cosy ...... Marlow, England .
.. doesn't try it on (Billy Connolly) .....................................

Chips wrote:
The garage is not connected to the house and is separated by about 3m of
paving/drive/whatnot.

Any suggestions for running the cable ?

Galvanised conduit (25mm).

Phil formulated the question :
wrote:
Phil wrote:

Chips wrote:
Well, the time has finally come to shift most of the computers out into
the garage (apparently).
Having already got enough power out there I need to put in a fat data
pipe to connect the lot to the house switch - cat5e will do nicely
because I have lots. Wireless is an absolute worst case scenario both
for speed and price and we need to connect to the servers for data
(video/music etc).

The garage is not connected to the house and is separated by about 3m of
paving/drive/whatnot.

Any suggestions for running the cable ?
I'm aware that pushing it through the same conduit as the power is a
no-go and I really don't want to dig up the drive unless I have to. I
suppose I could take it under a patio and through some of the lawn if I
must. On top of that I naturally don't want to spend very much time or
effort.

Chips.

--
-----------
Chips'll make it better.
-----------

Stick your cat5e in the conduit with the power - you won't get any
problems. In industry, it's rarely possible to get any separation of
the two - I've never had a problem.

It won't conform to the IEE wiring regulations though, they require
either 50mm separation or 'physical' separation which seems to mean in
practice a divider in the conduit/trunking.

I agree that it will almost certainly work perfectly well.

--
Chris Green

So? The IEE won't be inspecting it.
Presumably the power installation has already been passed.

It will work perfectly well, but that does not mean it is safe.
Probably the only inspection will be after someone is killed or injured
should the insulation fail and 240v get onto the CAT5.

--

Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

So? The IEE won't be inspecting it.
Presumably the power installation has already been passed.

It will work perfectly well, but that does not mean it is safe.
Probably the only inspection will be after someone is killed or injured
should the insulation fail and 240v get onto the CAT5.

--

Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

So two layers of double insulation laid in a conduit are going to fail?
At the same instant that someone makes accidental contact?

Osprey wrote:
I know that Comms wiring practise does not recc. for running copper
comms between buildings due to risk of electrical faults, lightning
strikes etc.

Ah. Thats prolly why my comms here is over 2 miles of copper..underground.

The approved way is fibre (as mentioned)

Why not use WiFi 802.11g will give you 54Mbs or up top 100 Mb if you
use HSM compatible devices.

Cos its crap?


Fibre is the best answer. To this particular set of specs.



or go nuts and use pre-N

wrote:

"Chips" wrote in message
...

snip

If you don't want wireless, then fibre is definately the way to go. If
100Mb/s would hack it, then a couple of D-link or ATI media converters
shouldn't cost too much.

Have a look at 'blackl box'

Google for UERL. they sell all te bits yoiuy need for something like this.

Certainly ethernet to fiber bridges are available..as long as there is a
switch at each end, you don't need anything more than that.

Biggest problem is termination at each end, but over that range a
perfect joint is not absolutely necessary.


If space in the conduit is a problem, make sure you use use fibe with
ST connectors these are only about 1/4" diameter and you can always
split the figure of eight "cable" so that you can feed them through
individualy. if push comes to shove, you could probably isolate,
disconnect and remove the mains, pull the fibre in and then pull the
mains back in.

Check the fibre is ok first!!

Guy King wrote:
The message
from Mike Dodd contains these words:

Any suggestions for running the cable ?

Anything wrong with wireless?


Other than the OP says he doesn't want it - worst case (cost / bandwidth).

Well, it's not /that/ expensive, and some systems do vast bandwidths
these days.

So how much is a wireless link that goes as fast as Gigabit ethernet?
Gigabit routers are now quite cheap (I bought my 8 port one for about
£70) and many motherboards have Gigabit NICs built in.

--
Chris Green

Phil wrote:

Chips wrote:
Well, the time has finally come to shift most of the computers out into
the garage (apparently).
Having already got enough power out there I need to put in a fat data
pipe to connect the lot to the house switch - cat5e will do nicely
because I have lots. Wireless is an absolute worst case scenario both
for speed and price and we need to connect to the servers for data
(video/music etc).

The garage is not connected to the house and is separated by about 3m of
paving/drive/whatnot.

Any suggestions for running the cable ?
I'm aware that pushing it through the same conduit as the power is a
no-go and I really don't want to dig up the drive unless I have to. I
suppose I could take it under a patio and through some of the lawn if I
must. On top of that I naturally don't want to spend very much time or
effort.

Chips.

--
-----------
Chips'll make it better.
-----------

Stick your cat5e in the conduit with the power - you won't get any
problems. In industry, it's rarely possible to get any separation of
the two - I've never had a problem.

It won't conform to the IEE wiring regulations though, they require
either 50mm separation or 'physical' separation which seems to mean in
practice a divider in the conduit/trunking.

I agree that it will almost certainly work perfectly well.

--
Chris Green

Phil wrote:


So two layers of double insulation laid in a conduit are going to
fail? At the same instant that someone makes accidental contact?

Murphy says yes!

The insulation can fail and be in a faulty state for years before the person
actually touches the live bits and gets killed.
It doesn't have to fail at the same time.

Why do you think you have routine inspections of equipment.
Its to limit the chances of a fault not being found before its too late.

Mains on cat5 will not cause any fault in the equipment as the cat5 is
isolated from the electronics by the pulse transformers at each end so any
such fault will remain hidden unless you look for it.

Phil wrote:
Chips wrote:

Well, the time has finally come to shift most of the computers out into
the garage (apparently).
Having already got enough power out there I need to put in a fat data
pipe to connect the lot to the house switch - cat5e will do nicely
because I have lots. Wireless is an absolute worst case scenario both
for speed and price and we need to connect to the servers for data
(video/music etc).

The garage is not connected to the house and is separated by about 3m of
paving/drive/whatnot.

Any suggestions for running the cable ?
I'm aware that pushing it through the same conduit as the power is a
no-go and I really don't want to dig up the drive unless I have to. I
suppose I could take it under a patio and through some of the lawn if I
must. On top of that I naturally don't want to spend very much time or
effort.

Chips.

--
-----------
Chips'll make it better.
-----------


Stick your cat5e in the conduit with the power - you won't get any
problems. In industry, it's rarely possible to get any separation of
the two - I've never had a problem.


I know this to be true having worked in numerous University retro-fitted
buildings. However, it's known to be unsafe and I know that it'd be
picked up when/if we sell - just my luck that is.

For those who are suggesting wireless - I have experience with it and I
know that it will present more hassles than it's worth. There are the
security issues too. No point in physically securing an outbuilding then
blasting your data to everyone within 100m.

Fibre looks best but I'm a bit iffy about some of the radii between here
and there. I'll go and check the specs.

Chips.

--
-----------
Chips'll make it better.
-----------

On Tue, 23 May 2006 08:26:44 UTC, "Phil"
wrote:

It won't conform to the IEE wiring regulations though, they require
either 50mm separation or 'physical' separation which seems to mean in
practice a divider in the conduit/trunking.

I agree that it will almost certainly work perfectly well.

--
Chris Green

So? The IEE won't be inspecting it.
Presumably the power installation has already been passed.

pedant
Especially since the IEE doesn't exist any more! :-)
/pedant

--
The information contained in this post is copyright the
poster, and specifically may not be published in, or used by
Avenue Supplies, http://avenuesupplies.co.uk

Phil wrote:

wrote:

Stick your cat5e in the conduit with the power - you won't get any
problems. In industry, it's rarely possible to get any separation of
the two - I've never had a problem.

It won't conform to the IEE wiring regulations though, they require
either 50mm separation or 'physical' separation which seems to mean in
practice a divider in the conduit/trunking.

I agree that it will almost certainly work perfectly well.

--
Chris Green

So? The IEE won't be inspecting it.
Presumably the power installation has already been passed.

You *might* have trouble if/when you sell the house, it would need a
thorough survey to spot it though. I agree totally that it almost
certainly wouldn't be an issue though.

--
Chris Green

On 23 May 2006 09:26:45 -0100, wrote:


Stick your cat5e in the conduit with the power - you won't get any
problems. In industry, it's rarely possible to get any separation of
the two - I've never had a problem.

It won't conform to the IEE wiring regulations though, they require
either 50mm separation or 'physical' separation which seems to mean in
practice a divider in the conduit/trunking.

And does this 'devider' also have to conform?

I mean you could thread yer Cat5 into some hosepipe but does that
provide electrical insulation to the correct standard? Whabout the
blue waterpipe, would that 'comply' even though it has much thicker
walls that a bit of 25mm plastic oval that probably would comply?


I agree that it will almost certainly work perfectly well.

Or howabout some armoured Cat5 .. isn't that then Cat5 in an extra
sheath, providing the "physical' separation". Or maybe the rules only
work if you buy the 'armour' loose and thread the cable through after
....?

As if any 250V is going to 'escape' from (say) some SWA, through 3
layers of insulation and a bundle of steel (earthed) wires then melt
through another two layers of insulation to get to the Cat5 copper
wires (that are optically isolated anyway) ... shrug.

Who actually has the stats re deaths through such failings and how
much greater is the risk to anyone else (other than the installer in
most cases) than say driving / smoking / overeating / stabbing or
boredom from reading through bucket loads of well meaning but OTT (for
most of us sensible people) regs ..?

All the best ..

T i m

T i m wrote:
On 23 May 2006 09:26:45 -0100, wrote:


Stick your cat5e in the conduit with the power - you won't get any
problems. In industry, it's rarely possible to get any separation of
the two - I've never had a problem.

It won't conform to the IEE wiring regulations though, they require
either 50mm separation or 'physical' separation which seems to mean in
practice a divider in the conduit/trunking.

And does this 'devider' also have to conform?

I mean you could thread yer Cat5 into some hosepipe but does that
provide electrical insulation to the correct standard? Whabout the
blue waterpipe, would that 'comply' even though it has much thicker
walls that a bit of 25mm plastic oval that probably would comply?


I agree that it will almost certainly work perfectly well.

Or howabout some armoured Cat5 .. isn't that then Cat5 in an extra
sheath, providing the "physical' separation". Or maybe the rules only
work if you buy the 'armour' loose and thread the cable through after
...?

As if any 250V is going to 'escape' from (say) some SWA, through 3
layers of insulation and a bundle of steel (earthed) wires then melt
through another two layers of insulation to get to the Cat5 copper
wires (that are optically isolated anyway) ... shrug.

Who actually has the stats re deaths through such failings and how
much greater is the risk to anyone else (other than the installer in
most cases) than say driving / smoking / overeating / stabbing or
boredom from reading through bucket loads of well meaning but OTT (for
most of us sensible people) regs ..?

All the best ..

T i m

Hear hear!

On Tue, 23 May 2006 13:56:00 +0100, Chips wrote:


Stick your cat5e in the conduit with the power - you won't get any
problems. In industry, it's rarely possible to get any separation of
the two - I've never had a problem.


I know this to be true having worked in numerous University retro-fitted
buildings. However, it's known to be unsafe and I know that it'd be
picked up when/if we sell - just my luck that is.

Possibly (my luck as well) ;-(

For those who are suggesting wireless - I have experience with it and I
know that it will present more hassles than it's worth.

Hmm, I know Wireless can have it's issues but set up properly can also
be fine (most folk don't actually need Terabit networking as they are
only browsing the web over it at ~2Mb/s) ?

There are the
security issues too.

True, but can be locked down pretty tight with some simple proceedures
... and unless you have any secrets ... ;-)

No point in physically securing an outbuilding then
blasting your data to everyone within 100m.

Indeed, so use a pair of directional aerials facing each other then
you will only be blasting data at a much narrower selection ;-)

Fibre looks best but I'm a bit iffy about some of the radii between here
and there. I'll go and check the specs.

Armoured Cat5, tack it to the fence, drape it out the way as a temp
measure .. It'll be easier to pull out the way when you move in 15
years time .. ;-)

http://tinyurl.com/pr97z

All the best ..

T i m

"Guy King" wrote in message
...
The message
from "nightjar" nightjar@insert my surname here.uk.com contains
these words:

My solution to running telephone, data and an air line between two
buildings a couple of metres apart was a piece of 100mm square 6mm wall
steel tube 3m above ground.

Don't you thing 1/4" thick walls was a bit OTT? To span a couple of
meters a bit of plastic drain pipe would have been fine.

The bloke in the factory next door used the stuff to make playground
equipment, so it had the advantage of being free.

Colin Bignell

The message
from "nightjar" nightjar@insert my surname here.uk.com contains
these words:

The bloke in the factory next door used the stuff to make playground
equipment, so it had the advantage of being free.

Don't suppose you've got any more? I've used a fair bit to make the
climbing frame, but the kids keep pestering me to get the welder out and
add more.

--
Skipweasel
Pay no attention to that man behind the curtain.

T i m wrote:

As if any 250V is going to 'escape' from (say) some SWA, through 3
layers of insulation and a bundle of steel (earthed) wires then melt
through another two layers of insulation to get to the Cat5 copper
wires (that are optically isolated anyway) ... shrug.

Cat 5 is not optically isolated.
Ethernet uses pulse transformers.
I hope the rest of what you said is correct.


Who actually has the stats re deaths through such failings and how
much greater is the risk to anyone else (other than the installer in
most cases) than say driving / smoking / overeating / stabbing or
boredom from reading through bucket loads of well meaning but OTT (for
most of us sensible people) regs ..?

All the best ..

T i m

Chips wrote:
snip
I know this to be true having worked in numerous University retro-fitted
buildings. However, it's known to be unsafe and I know that it'd be
picked up when/if we sell - just my luck that is.

It's known to be unsafe - for very small values of 'unsafe'.

Yes, if the rats chew the cables, or the mains cables insulation melts
through, the network cabling can become live.
How likely is that in practice though.
If it was me - and in fact it is - as I'm doing a similar thing.

Buy two small network hubs.
Fit these inside the boxes where the conduit terminates.

Connect the shield of the cat5 cable to the earth of the RCD, in such a
manner that if any current flows in the shield, it'll trip off the RCD.

Connect the outside world to the cable through the conduit via the hubs.
Cat5 hubs are electrically isolated, with typical isolation ratings of a
kilovolt or so on the isolation transformers.

Stick a label in there saying "In the event of multiple faults, this
network cable may be live".

Phil pretended :
So two layers of double insulation laid in a conduit are going to fail?
At the same instant that someone makes accidental contact?

Quite possibly, that is why the regulations do not permit the mix of
the two. It doesn't actually require metal to metal contact, all it
needs is a nick in the 240v insulation, nick in the Cat5 insulation add
a little rain water in the conduit and you have enough conductivity for
someone to be killed.

That's just not going to happen.

So you would be happy to let your kids handle such a cable -
deliberately installed so as to ignore the regulations intended for
their protection?

--

Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

"Phil" wrote in message
oups.com...

So two layers of double insulation laid in a conduit are going to fail?
At the same instant that someone makes accidental contact?

Quite possibly, that is why the regulations do not permit the mix of
the two. It doesn't actually require metal to metal contact, all it
needs is a nick in the 240v insulation, nick in the Cat5 insulation add
a little rain water in the conduit and you have enough conductivity for
someone to be killed.

That's just not going to happen.


Actually, having been the poor sod up a telephone pole, yes, it can and
does happen - and the pole top has a pretty good earth (for lightning
protection) to touch along with the (live) 'phone cable. The 'phone
exchange, however, has fuses in line, so the line stays up at 240Vac all the
way there - hence BT and others getting very shirty (sp?) about unapproved
'phones that connect to the mains, etc. I used to delight in removing and
rendering safe (yanking out the cables, if possible with PCB damage)
unapproved 'phone equipment, same for non-compliant cabling [1], at least
for a couple or more months after I landed with certain tender parts of my
anatomy on a pole step after getting a 240V belt up my arm...

Dave H.
(The engineer formerly known as Homeless)

[1] Including one where they'd used the spare pair in a mains SWA cable, all
the cores terminated in a choc-block connector, to run a 'phone line to the
garage... and called BT becauses there was a "terrible hum on the line",
similar where the 'phone wiring had been stapled-gunned down - with the
staple passing through both the 'phone cable and the live conductor of a
tacked-down mains flex...

"Guy King" wrote in message
...
The message
from "nightjar" nightjar@insert my surname here.uk.com contains
these words:

The bloke in the factory next door used the stuff to make playground
equipment, so it had the advantage of being free.

Don't suppose you've got any more? I've used a fair bit to make the
climbing frame, but the kids keep pestering me to get the welder out and
add more.

He retired a couple of years back, so I don't have access to the stuff
anymore.

Colin Bignell

On Tue, 23 May 2006 18:46:19 GMT, "dennis@home"
wrote:

T i m wrote:

As if any 250V is going to 'escape' from (say) some SWA, through 3
layers of insulation and a bundle of steel (earthed) wires then melt
through another two layers of insulation to get to the Cat5 copper
wires (that are optically isolated anyway) ... shrug.

Cat 5 is not optically isolated.
Ethernet uses pulse transformers.

Ok, 'isolated' .. (the line drivers i used to repair were 'optically
isolated', typically run over what used to be called an EPS8 ccts I
think?) but the spirit of what I was saying remains.

I hope the rest of what you said is correct.

Pass? ;-)

All the best ..

T i m

Harry Bloomfield wrote:
Phil pretended :
So two layers of double insulation laid in a conduit are going to fail?
At the same instant that someone makes accidental contact?

Quite possibly, that is why the regulations do not permit the mix of
the two. It doesn't actually require metal to metal contact, all it
needs is a nick in the 240v insulation, nick in the Cat5 insulation add
a little rain water in the conduit and you have enough conductivity for
someone to be killed.

That's just not going to happen.

So you would be happy to let your kids handle such a cable -
deliberately installed so as to ignore the regulations intended for
their protection?

--

Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

If any of the mains-propelled electrons go walkabout I expect (and test
that) certain events to occur to turn off the supply, this event being
asynchronous with anyone touching anything.

On 24 May 2006 01:12:55 -0700 someone who may be "Phil"
wrote this:-

If any of the mains-propelled electrons go walkabout I expect (and test
that) certain events to occur to turn off the supply, this event being
asynchronous with anyone touching anything.

And what events are those?


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

You missed the point ... the exchange running copper to you is one
thing, it's earthed at a single point.
If you run copper comms from your house to an out building there is a
proscribed risk due to linking of earth paths in the event of the mains
losing it's earth ... or in event of lightning strike.

Well proven even before WWII: even buried wires suffer from direct
lightning strikes like overhead cables. Even before WWII, both
underground and overhead wires were properly earthed when entering a
building - and therefore damage from lightning was routinely averted.
Technology is that old and that well proven. An October 1960 paper in
Bell System Technical Journal from Bodle and Gresh desribes standard
protection. Their question was whether buried and overhead wire
protection - generations standard even before 1960 - was sufficient for
semiconductors:
The problem of protecting apparatus against lightnng surges
from connection transmision facilities has become more
complex with the use of solid state devicesin apparatus
design. ... The results of this field investigation and
supplemental laboratory surge tests indicate that in well
shielded underground cable pairs, electrical surges do not
exceed approximately 90 volts peak ... In aerial and buried
cable, however, transistorized apparatus requries protection
up to the full sparkover potential ... to about 600 volts peak.

Those who never learned basic protection techniqes then recommend
expensive solutions such as fiber optics.

Any connection between buildings - as has been standard practices for
most of the past 100 years - enters and earths all utility and
communication wires at a common service entrance. Makes little
difference if wire is 2km above or below earth. It still requires well
proven and standard protection.

The Natural Philosopher wrote:
Osprey wrote:
I know that Comms wiring practise does not recc. for running copper
comms between buildings due to risk of electrical faults, lightning
strikes etc.

Ah. Thats prolly why my comms here is over 2 miles of copper..underground.
...

Fibre is the best answer. To this particular set of specs.
...