Elec wiring

[ss]

Following on from my previous post in trying to find the main feed to these lights. I have linked a pic, edited to make it smaller but shows the layout, and the green lines are my non electrical assumptions on how it maybe wired.

A couple of points: the ceiling has 2 layers of plasterboard and it appears the way the holes for the halogens have been drilled that they have been put in place from through those holes but cant be sure. I am pretty sure the main feed comes from the point of where I have indicated the light switch. I tried a mobile phone for pics but not giving me much help.

Some of the transformers have 2 cables attached to them (as indicated) and one of them is a different type of transformer. To me it looks as if from the main feed there are two seperate feeds which in turn supply 2 halogens each. Hope I am making sense with this.

Looking for advice on how to move forward with this as I want to remove the halogens and put a central light in their place. Should I try gently tugging at the wiring?

[Ash Burton]

I can't find your previous post so i may not have the full picture.

Is the 'double cabling' you refer to 'loop in/loop out' or do you mean 2 cables in parallel?

Do you have access to the switch, if so is it a normal 5A single pole type or double pole? This should tell you if the lights are supplied by the cable from the switch (in which case that could be used as the source of supply for your new central light) or if it's just a switch wire circuit (then you need to trace where that goes and that will reveal the supply source for the spots).

--- news://freenews.netfront.net/ - complaints: [e-mail] ---

[ss]

I can't find your previous post so i may not have the full picture. "help with tracing wiring"

I have access to the switch which is outside the toilet I think I know part of the route where it gets from the switch to the toilet ceiling void but trying to find the connection point in the toilet ceiling void (with minimal damage to the ceiling) so I can disconnect the halogens and then reconnect a central light.

Not sure if single or double pole but when the switch is off I get no reading from a non contact voltage detector at the halogen bulb wiring. I can have a look inside the switch tomorrow if need be.

Two cables in parallel, If you think of the transformer at one end two wires go in probably 1 in and 1 out, at the other end of the transformer the wire goes to the halogen lamp, so thats 3 wires in total. That only applies to 2 of the transformers the other 2 just have 1 in to feed the transformer and 1 out to feed the halogen lamp.

The diagram below probably explains it better, the red wiring is my best estimate as to how I think it is wired, I am trying to get access to the `blue circle` but that is me assuming thats where the connections in the void are made, and again assuming there is enough slack.

[Roger Mills]

Can you reach the transformer nearest the switch through its lamp hole, and is there enough slack on the cables to get at the connections?

If you disconnect the two mains input cables, one should be live when the switch is turned on, but the other one won't be. The one which is live can provide a feed to your new central light. You'll need to join another T&E cable to it, end to end - and feed that through to where you want your central light. Feeding it through will be your greatest challenge because it's very likely that there will be one or more joists in the way. Having said that, it's likely that some of the inter-transformer cables already go through the joists - so you may be able to re-deploy those once you've disconnected the transformers.

Don't expect it to be easy! My lounge is L-shaped and I have 12 downlighters in 3 groups of 4 with one transformer for each group. I installed the transformers and wiring while the ceiling was down - but planned for the transformers to be accessible through the lamp holes for maintenance purposes. In the event, when a transformer failed, I couldn't get at the bl**dy thing because I'd made too good a job of clipping the wires in place - and I had to take up some floorboards in the room above in order to replace it.

[ss]

I can get to the transformers, so I will gently tease as much cable out as I can.

"Feeding it through will be your greatest challenge" Damn I never thought of that, maybe I can tape a new wire to the existing wire and pull it through, if I get that far. failing that attacking the ceiling will be next :-(

[Brian-Gaff]

No don't break them off or you will end up with no lights at all. Myself I'd concentrate on how to wire up the new light, and leave the rest in place and just cover over the holes. If you know where the switched supply is, then once the new light goes on and off with the switch, just remove the connections too the other lights and pretend they are not there!

Brian