Choice of wire diameter for doll's house?

Question

I'm constructing a 1:12 scale doll's house and I'd like to use enamelled wire run within the walls for lighting. Each room would have its own circuit controlled through a switch and then to a common 12V supply.

Some of the lamps will be LED and some will use filament type bulbs (depending on what's available). Maximum number of lights per circuit would be something like 6 eg. 2 wall lamps, 2 ceiling lamps and perhaps a table lamp or two. They'll all be wired in parallel.

I chose solderable enamelled wire as it's single core and easy to solder to miniature fittings. There also won't be a problem with insulation shrinking back when soldering. The conductors will be lightly twisted, run in a 3mm channel cut into the MDF walls and 'back filled' with plaster.

Each circuit would be fused, perhaps 750mA? Maximum length of run might be 1 metre.

Could I get some ideas on what might be a suitable conductor size for this project? I already have some 24B&S 0.5mm dia. wire handy but can't seem to find consistent data regarding the current capacity (with information varying between 1.4A and 300mA). Something with a comfortable capacity of 1A or 1.5A maybe?

Thanks so much for your advice.

Answer 1

I always like to consult this chart https://www.powerstream.com/Wire_Size.htm So I would go with at least 27 gauge wire. It says it has a maximum current of 1.7 amps. This may also be different depending on how easily your wires can cool. If they are in plaster that may insulate them so you may have to go thicker. If you are using 24 Gauge I would think that would be fine.

Another note, if you use DC that will generate more heat, if you are only powering LED and incandescent bulbs why not use AC? AC will allow the wires to stay cooler. The LEDs may flicker but it shouldn't be too noticeable. If you have a 12 volt AC adapter that keeps the output AC I would try that out.