What do I need to power a Christmas village with mains instead of batteries and in a single circuit?

Question

I should start by saying that I'm fairly new to this world but I already know my way around a breadboard.

I already made a sort of mock-up of what I need in a breadboard with a few LEDs, resistors, and a 9 V battery + breadboard power adaptor.

Essentially, the LEDs were set in parallel and with a resistor each (standard LEDs with a 220 ohm resistor, 5 V from the breadboard power adaptor). This way I can power off or remove any of the LEDs (or Christmas village houses) and have the others continue to work.

I also added a potentiometer to control how bright the LEDs are.

Now, my problem is that I don't really know what components I need to bring this into the real deal.

I'm not sure if links are OK, this is the shop that I use in my country, so it's easier for me to show you what I'm talking about

I know I'll need a power supply to the mains, something like this, perhaps? -> https://mauser.pt/catalog/product_info.php?cPath=23_66_884&products_id=035-3814

It is a 3 V to 12 V variable power supply with 1500 mA. I'm inclined to this one so I can better control how much power goes through and I don't burn anything. Would a USB adapter be good enough? (5 V 1.35 A)

Each Christmas village house is usually powered by two to three 1.5 V AA batteries, so about 4.5 V each. At the moment I have four but intend to have more in the future.

So, my goal is to have them all in parallel, with a resistor? Maybe so I don't burn them, a potentiometer for each so I can control the brightness and some sort of easy plug that I can use to plug them in or out without affecting the overall circuit.

I think I need something like this (maybe missing resistors between potentiometer and plug terminal):

Does this make sense, is it correct, and is it possible to help with the name of components and voltage, amperage and resistance values?

I'm planning on getting wire, the plugs, the terminal (can't find the name of it), the potentiometers and the plug. https://mauser.pt/catalog/product_info.php?products_id=011-2291 - Is there any type of terminal that I can use to plug a lot of these?

https://mauser.pt/catalog/product_info.php?products_id=005-1032 - I can only find low wattage potentiometers, so I'm not sure if this is the correct way to control the voltage going to each house.

Please let me know if I'm forgetting something or if I have anything wrong or there is anything else you want me to clarify.

TLDR: I want to convert battery-powered Christmas village houses so I can use a power supply/plug to the wall, and have a way to turn them all individually or all at once so I don't have to pick them up one by one whenever I want to switch them on. If possible, it should be future proof to add more houses.

PS: Is there any website or software, preferably free, that allows to test this type of circuit?

Answer 1

If you use that circuit what will happen when you turn any of the potentiometers all the way down is the power supply will be shorted out and the pot will likely burn up. The wipers are connected to positive and one end is connected to negative so turning the pot down connects those through a very low resistance.

If you want to vary the voltage you would connect positive to one end of each pot, negative to the other end, and the wiper to the LED. Even then it's likely to not work very well. You would need to use low value pots and that would waste a lot of power as heat. You could use low value pots with just one end connected to positive and the wiper connected to the LED, that would act as a current setting. you would need to have a limiting resistor in series and then a pot with a value that would be enough to limit the current further to the point that the LED is very dim.

^{simulate this circuit – Schematic created using CircuitLab}

Something like this may work, but the control isn't likely to be very linear and you may not be able to completely dim the LEDs. You would probably have to experiment a bit to find the best value for the pot, and to completely shut an LED off may require a switch in series with each one.

A better way to do it is with PWM control where the LED is switched on and off very quickly and the brightness is determined by the ratio of on to off times. This requires a bit more know-how to implement yourself, but there are a lot of pre-made LED controller modules available, so you might look into those.