This is how I did it
Here is a list of the steps I take to connect my electrical fittings to the power supply. It assumes a couple of things. Firstly, you are wiring an English-style dollshouse which opens at the front, so you are able to take all your wires to the back of the house. Secondly you don't care how it all looks when its connected up because (a) the back will never be seen or (b) like me, you are going to cover it all up with a piece of thick card or thin ply cut to the size of the back of the house, using magnets or Velcro tabs, mounted on some spacers.
1. Check that all the wires are at the back of the project ready to go
2. Screw your power strip to the back of your project remembering to use the four little plastic spacers
3. Select the wire you want to connect and remove about an inch of plastic sheathing to reveal the copper wires. You will need to separate the two sides of the wire. If you are lucky you can make a small snip with a sharp knife or scissors and then pull the two strips apart. More often than not this doesn't work too well and bits of wire are exposed: in that case there is nothing for it but to cut down the centre channel between the sides very carefully. If your wire is going to need extending you will need to have about two inches of the plastic separated. You need this to put the heat-shrink tubing on to cover the join. Almost all of my 32 lights did need longer wires to reach the power strip.
4. Does it need extending to reach the power strip? If so, measure how much more wire you will need, cut from the roll and bare the ends on this piece as you did for the one that is attached to the light/fireplace/whatever. This time you won't need an extra couple of inches of plastic sheathing pulled back; about half an inch to an inch will do.
5. Thread heat-shrink tubing on each wire where you have the two inch length separated
6. Join the wires from your project piece to the add-on wire. Strictly speaking I think this should be soldered, but I have never done that. I am just extremely careful to note that they are successfully joined to each other and then I depend on the tubing (after it has shrunk) to keep them that way.
7. Use a hair dryer to shrink the tubing. Don't be nervous about this, it needs to be held very close to do the job. I had two kinds of tubing - some clear, soft sort, in a long coil which I bought somewhere by the metre and a packet of black pre-cut tubes. The clear soft tubing melted more quickly and more efficiently than the black.
8. Tape down the wire firmly at its exit point. I do this to help prevent any movement on the position of the lamp or ceiling light or fire. They can easily be bumped when you are dressing a room and they are best fixed in place as much as possible on both sides.
9. Label the wire. Heaven forbid that anything needs attention in the future but if it did you really need to be able to find the pesky item easily.
10. They are now all ready to be taken to the power strip. Before I do this I laboriously check that each one is still working, using a 9v battery. ** I check the light is working at every step of the process because I want to know what stage a 'fault' is at, if one presents itself. For example if I skipped this last set of checks and a light didn't come on when the the power was attached I wouldn't know if the problem was a bad joining of an extension wire or a poor connection to the power strip. This is where you do need another pair of eyes - not possible to be at the back and front of the house at the same time.
11. Calculate how many in each terminal. I have 32 wires on this project and the power strip has ten terminals. There is actually twenty little holes because they have a positive and negative marking for each number. More about this later. I, therefore, need to put three wires into each pair of holes eight times (24 wires). The other eight wires will then be joined into two sets of four (8) for the other two terminals. This totals 32 wires reasonably divided across the ten terminals.
12. Group lights together in threes and fours as explained and twist the wires together securely. This bit is easy to do but quite hard to explain. You have pulled your item's wire apart into effectively two wires - let's call one wire a right-hand wire and the other the left hand wire. In reality each of those is actually made up of three little copper wires not much thicker than a hair. For our purposes they are being treated as if they were a single wire. So what you have to do is take all the right hand wires from the wires you have decided to connect up and twist them together very carefully. Click on this picture to enlarge it for a clearer view. You then do the same for the three left-hand wires.
You only need a very short length, enough to go into the hole in the terminal. You don't want any exposed wire showing above the terminal block.
13. Push the wires firmly into the power strip all the way in until only the plastic is showing above the hole. The strip comes with the screws undone and the holes open. occasionally they made need unscrewing a little more if you are having difficulty getting the wires in. Push one collection of wires into the plus and the other collection into the minus sides of a number and screw the screw in firmly to hold the wires in place and make the necessary electrical contact. You can give them a very gentle tug to be sure they are in tightly.
14. Polarity. The vast majority of electrical items for 1/12th miniatures have no polarity and so either of the two wires can go in the plus or the minus side without any problem. Occasionally you may buy something which comes with some marking on the wire suggesting that isn't the case. The positive wire could be marked red and the negative in black or blue. I used some LED lights that were marked in this way. You must be sure to join the negative wires only to other negative wires and the positive wires only to other positive wires. They must then go into the terminals accordingly. The negative goes into the hole with a minus sign and the positive into a hole with a plus sign. My other half said it probably wouldn't matter in this case but I wasn't for risking it. It takes no longer, just a little bit of extra paying attention.
15. Connect to the transformer. Most transformers and power strips now come with a simple 'plug-and-play' connection like this one. if they don't they will have very clear instructions as to how to connect one piece of kit to the other.
16. Plug into your wall socket, switch on and stand back in amazement
Having struggled my way through this over the last few days I can't in all honesty say it is an easy job or one that I don't mind doing. It is fiddly and frustrating and annoying almost every step of the way but by the time you have committed a good deal of money and have some nice items requiring power, the choice to do it or not is no longer an option.
If you have about twelve or less items to light it is probably easiest to just stay with the plastic power strips and extend any wires using plug-in extensions. Maybe even up to 24 items and using two power strips to keep your life very simple.
You could, of course, use this method for any size project by just adding in more strips but I think there would be a point where you will need more than one transformer and very soon it becomes very cumbersome.
I do think that once you are messing around with something like twenty or more things needing power and you are on the round-wiring rather than tape path, the only way to go is the Small World power strip I use.
There are no shortcuts or easy ways to do any of this be it copper tape system or round-wiring, white plastic power strips or the strip I am using - you will just have to flog away at it until it is done. I swear, very close to the end of the chore I began to think about whether it would have been a good idea to hire an electrician and let them fiddle about with it!! Wonder if you could..............
I can honestly say, touch wood, my lighting has always worked for me without any 'it hasn't lit' issues to sort out and not even so much as a bulb going on the blink in the following months. I do read frequently that some folk are having problems with things not working or going on the blink and can only imagine how extremely annoying that must be. I would hate to have to sort out a lighting issue. On that cheerful note, I wish you happy lighting. Like childbirth, you quickly forget the pain once it is over and you are gazing at your beautiful creation.
I love peeking through the windows of dolls houses and its even more interesting at night.
I will be recording each room's lighting tomorrow (for me really) so that's probably a post you can skip.
** I have just been told that some Chinese-made 3v lights don't like being tested on a battery and will 'blow' I have never been unlucky this way but I thought I should pass this on.