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Penners
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I've often seen exposed cables on oak beams. Painted roughly the same colour as the beam, they don't look too conspicuous (to me, anyway).
An electrician would probably tell you that, for maximum safety, you should enclose the cables within trunking. I suspect, however, that this would tend to be more visually intrusive - even if the trunking is painted to match the beam.
An electrician would probably tell you that, for maximum safety, you should enclose the cables within trunking. I suspect, however, that this would tend to be more visually intrusive - even if the trunking is painted to match the beam.
chuckey
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Got the same problem in one place. As this is a lightinng pendant, I'll be using gold coloured cabling back to a plastered in box with a plain cover.
In an old house I worked on, the original (rubber) wiring was sat between two 3/8" square pieces of beading with a cover nailed over the lot. The cover was a piece of 1 1/2" X 3/16" wood with a beautiful moulding planed into it.
If you are hanging fitting from beams, please not do as the electricians still do round here, bore a 3/4" hole from the centre of the beam at an angle of 45 degrees out of the side of it. You wreck the strength of the beam and that hole will be there forever and if the light fittinng is large its "ceiling rose" will be too wide for the beam anyway. Make a semi circular piece of wood the depth of the beam with a hole(for the cable) down the centre of the semi circle. Mount it on the side of the joist, these screw hole will not be visible to room users.
Frank
In an old house I worked on, the original (rubber) wiring was sat between two 3/8" square pieces of beading with a cover nailed over the lot. The cover was a piece of 1 1/2" X 3/16" wood with a beautiful moulding planed into it.
If you are hanging fitting from beams, please not do as the electricians still do round here, bore a 3/4" hole from the centre of the beam at an angle of 45 degrees out of the side of it. You wreck the strength of the beam and that hole will be there forever and if the light fittinng is large its "ceiling rose" will be too wide for the beam anyway. Make a semi circular piece of wood the depth of the beam with a hole(for the cable) down the centre of the semi circle. Mount it on the side of the joist, these screw hole will not be visible to room users.
Frank
PVC cable can be painted with gloss topcoat, which bonds well to the pvc. Theres no need for trunking.
If youre determined to achieve invisibility, LV lighting can use enamelled copper wire, which is way smaller than mains T&E, and can often be completely hidden.
NT
If youre determined to achieve invisibility, LV lighting can use enamelled copper wire, which is way smaller than mains T&E, and can often be completely hidden.
NT
Low voltage lighting systems may be safe to touch due to the reduction in voltage. However, for the same power output, the current has to go up by the same ratio that the voltage has gone down. This means that the cable will have to have a larger copper core than T&E.
As an example, a single 240V 100W bulb requires 0.42A to drive it. Five 20W halogens on the other hand, running at 12V requires 8.3A to drive them.
Due to the high currents, it is important that there isn't any danger of shorts / weak joints due to the possibility of over heating leading to fires. I would be cautious in using enamelled wire for this reason.
As an example, a single 240V 100W bulb requires 0.42A to drive it. Five 20W halogens on the other hand, running at 12V requires 8.3A to drive them.
Due to the high currents, it is important that there isn't any danger of shorts / weak joints due to the possibility of over heating leading to fires. I would be cautious in using enamelled wire for this reason.
Penners
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I've always been worried by those LV lighting kits that power a row of lamps from two parallel uninsulated catenaries. All very stylish, I'm sure, but the risk of short circuits must be ever present.
I think that people are lulled into a false sense of security by the fact that they can touch the conductors without harm.
I think that people are lulled into a false sense of security by the fact that they can touch the conductors without harm.
chuckey
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MdB, was that in Butler's leaving party in "On the Buses"? 
Frank
Frank
MdB said:
correct so far
No, for 2 main reasons.
1. T&E has ampacity way beyond the light fitting it supplies
2. LV cabling can be split into more than one feed - and its best to do so
1mm^2 in pvc is good for 16A when surface wired, so 0.25mm^2 has enough ampacity for half that much lighting, ie when using 2 transformers. 0.25mm^2 is very small, in practice one would and can use bigger.
Cue voltage drop discussion.
the type of insulation used does not affect copper to copper joints. The currents in use can not be considered 'high', unless you also regard all mains cabling as 'high' current. Shorts are not a significant danger with LV lighting as 12v transformers have overcurrent limitation and protection.
The one caveat with enamelled copper is the insulation tends to deteriorate if moved, so it should either be fixed in such a way as to make no movement possible, or the 2 wires run not touching. Putting it in cracks and filling over is a great way to make it disappear.
NT
electricianid
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You cant beat MICC for aesthetics, assuming you have the budget and a spark with the tools/knowhow, you can also achieve higher loading/csa than with T&E, or any other type of cable that I'm aware of.