In message , Tim Watts
writes
On 08/12/10 08:45, ARWadsworth wrote:
wrote:
I think the time has finally come when I may get to convert the
"storage room" at the end of the garage into a "workshop" as was
intended when the building was erected about 10 years ago. With that
in mind I need to wire up the electrics (there's already a CU there,
currently supplying lighting and a single socket for the garage).
Given the 'workshop' element, I want to fit one ring of
surface-mounted metal-clad sockets (probably these:
http://preview.tinyurl.com/2vda3wg) and was going to use
surface-mounted PVC conduit (it's a single-thickness block-building).
Thing is, although I've done plenty of wiring before I've never used
conduit and am not entirely sure how to go about it: I could really
use an on-line how-to-do-it guide but can't find one - is there such
a resource around?
To be honest I have no intention of taking this to Building Control
but still want the work to be up to standard. Is PVC conduit
considered acceptable in this sort of environment? (We're talking a
very low-key, domestic, end-of-garage-type workshop, not one with
lots of massive machine tools etc).
Do you have to use single-core wires; ie, will two 2.5mm2 T&E cables
not fit down a standard 20mm PVC conduit? And/or does that present
potential overheating problems? I'd rather not have to use
single-core stuff if I can help it, as I've got plenty of T&E, and
you can only buy the singles in 100m lengths AFAICS.
How do the couplers, male and female adaptors etc work in connecting
up conduit boxes and socket boxes etc? Probably be obvious when I've
got them in my hands, but I'm putting together an on-line shopping
list...
As I say - a simple Noddy guide is probably what I need!
Thanks
David
Are you wanting the cable in conduit in all the workshop or just for the
drops down to switches and sockets? If it is all conduit then you need to
use single cables not T&E.
I would not attempt to pull T&E down anything other than straight runs.
Can be done if the bends are very gentle IME - but the bugger are any
joins with straight couplers - there is always a lip the cable end
snags on - can take some fiddling with pulling on a tape at one end and
pushing the cable gently at the other.
The adaptors eg http://www.tlc-direct.co.uk/Products/MT20FMAB.html are used
for connecting up to socket backboxes etc. Undo the nut on the adaptor, fit
into the hole and screw the nut back on. The conduit then just pushes into
the adaptor. You do not use these adaptors for connecting the conduit to
conduit boxes and bends, the conduit just shoves into those without the need
for adaptors.
I often just run a big piece of trunking around the garage between the
ceiling and wall and just use conduit for the drops (a 20mm hole cutter is
needed). That way I can use T&E and any additions later are easy. It is a
damn site easier and faster than using conduit all over the place.
I like that approach - it is what they seem to do here (Imperial
College) a lot - sometimes using all plastic, sometimes galvanised
trunking and steel conduit (depending on the environment) - but always
that sort of layout. I would add that is for final drops - all the
feeders from 32A upwards tend to be SWA.
AOL
Galvanised steel 2" trunk. Use stranded singles. Trap clear of lid with
strips of polystyrene etc. foam.
You can purchase corners but I usually *angle grind* out the sides and
fold to 90deg.
Twin metal clad socket boxes stood off on two straight conduit couplers
secured with two brass bushes.
Run a separate earth wire.
Future proof:-)
Still some MICC around but I don't see anyone installing it new anymore.
Not surprising!
regards
--
Tim Lamb