Hi

We've just bought a new house which has a summer house at the bottom of
the garden about 25 metres from the main house building. The previous
occupants kindly installed a power supply to this building using 2.5
T&E buried in two inches of soil and clipped to the fence posts... I
won't even tell you what was done at the consumer unit end!

Needless to say, I intend on immediately ripping this out and
installing SWA in the correct manner - however, I also need to run some
cat5, alarm cable and a satellite feed down there.

Can someone suggest what the best kind of ducting to use for this job
would be? Also, if the said ducting is providing full mechanical
protection of the cable, would that mean that I could run the power
cable through the duct and avoid the need for a separate SWA cable?

Many thanks,

Steve

stevelup wrote:
Hi

We've just bought a new house which has a summer house at the bottom of
the garden about 25 metres from the main house building. The previous
occupants kindly installed a power supply to this building using 2.5
T&E buried in two inches of soil and clipped to the fence posts... I
won't even tell you what was done at the consumer unit end!

Needless to say, I intend on immediately ripping this out and
installing SWA in the correct manner - however, I also need to run some
cat5, alarm cable and a satellite feed down there.

Can someone suggest what the best kind of ducting to use for this job
would be? Also, if the said ducting is providing full mechanical
protection of the cable, would that mean that I could run the power
cable through the duct and avoid the need for a separate SWA cable?

If it were me, I'd run the SWA and a separate run of blue MDPE pipe. I
would probably use 25mm (but 32mm is also available). Run the cat5,
alarm and sat cable down there. MPDE is very cheap, readily available,
and designed for burying in the ground. It will usually withstand a
spade hitting it but you need to decide how likely this is and how deep
you bury it! Use pipe marker tape above the pipe to help avoid any
accidents though.

Jon.

Tournifreak wrote:
If it were me, I'd run the SWA and a separate run of blue MDPE pipe. I
would probably use 25mm (but 32mm is also available). Run the cat5,
alarm and sat cable down there. MPDE is very cheap, readily available,
and designed for burying in the ground. It will usually withstand a
spade hitting it but you need to decide how likely this is and how deep
you bury it! Use pipe marker tape above the pipe to help avoid any
accidents though.

Cheers,

That seems like a sensible plan!

Steve

On 31 Aug 2006 03:54:30 -0700 someone who may be "stevelup"
wrote this:-

Can someone suggest what the best kind of ducting to use for this job
would be? Also, if the said ducting is providing full mechanical
protection of the cable, would that mean that I could run the power
cable through the duct and avoid the need for a separate SWA cable?

That is allowable if a) the cables are in separate compartments or
b) the extra low voltage cables are insulated to low voltage (mains)
standards.

Even if done by allowable methods you would get mains hum induced on
the extra low voltage circuits due to the close proximity. Separate
the runs even slightly and the problem is much less.

I would add a telephone cable. Hard wiring a telephone point
provides further options for very little cost.


--
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

In article om,
stevelup wrote:
Can someone suggest what the best kind of ducting to use for this job
would be? Also, if the said ducting is providing full mechanical
protection of the cable, would that mean that I could run the power
cable through the duct and avoid the need for a separate SWA cable?

Power needs to be in a separate duct from signal cable - or in a special
type designed for both which keeps them apart.

--
*Honk if you love peace and quiet.

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

Dave Plowman (News) wrote:
In article om,
stevelup wrote:
Can someone suggest what the best kind of ducting to use for this job
would be? Also, if the said ducting is providing full mechanical
protection of the cable, would that mean that I could run the power
cable through the duct and avoid the need for a separate SWA cable?

Power needs to be in a separate duct from signal cable - or in a special
type designed for both which keeps them apart.


In general, yes - but if the power cable is SWA, it would surely be hard
to argue that power and signal conductors were not sufficiently
separated for safety purposes (hum and noise pickup being a separate
issue).


--
Ian White

"Ian White" wrote in message
...
Dave Plowman (News) wrote:
In article om,
stevelup wrote:
Can someone suggest what the best kind of ducting to use for
this job
would be? Also, if the said ducting is providing full mechanical
protection of the cable, would that mean that I could run the
power
cable through the duct and avoid the need for a separate SWA
cable?

Power needs to be in a separate duct from signal cable - or in a
special
type designed for both which keeps them apart.


In general, yes - but if the power cable is SWA, it would surely be
hard
to argue that power and signal conductors were not sufficiently
separated for safety purposes (hum and noise pickup being a
separate
issue).


Yes, but how would someone know in the future that the SWA is low
voltage and not multi core extra low voltage (data / coms etc.) like
the other cables?...

Jerry wrote:

"Ian White" wrote in message
...
Dave Plowman (News) wrote:
In article om,
stevelup wrote:
Can someone suggest what the best kind of ducting to use for
this job
would be? Also, if the said ducting is providing full mechanical
protection of the cable, would that mean that I could run the
power
cable through the duct and avoid the need for a separate SWA
cable?

Power needs to be in a separate duct from signal cable - or in a
special
type designed for both which keeps them apart.


In general, yes - but if the power cable is SWA, it would surely be
hard
to argue that power and signal conductors were not sufficiently
separated for safety purposes (hum and noise pickup being a
separate
issue).


Yes, but how would someone know in the future that the SWA is low
voltage and not multi core extra low voltage (data / coms etc.) like
the other cables?...


Fair point about marking the cable; but remember what "SWA" stands for.
Earthed steel wire armouring gives far more protection and segregation
than the token plastic rib inside a divided conduit.



--
Ian White

"Ian White" wrote in message
...
Jerry wrote:

snip

Yes, but how would someone know in the future that the SWA is low
voltage and not multi core extra low voltage (data / coms etc.)
like
the other cables?...


Fair point about marking the cable; but remember what "SWA" stands
for.
Earthed steel wire armouring gives far more protection and
segregation
than the token plastic rib inside a divided conduit.


Segregation of low and extra low voltage services is the issue here,
not protection of the cable, a divided conduit gives far more
segregation than just relying on insulation and (possibly in the
future) missing cable markings.

Hi

Thanks for all the input. I'm definitely going to run the power and
data separately - I do like the idea of using HDPE water pipe as cheap
trunking.

Cheers,

Steve