I have a project DMX splitter. There should be 3 outputs. Every output has to have own power supply and be totally isolated.
https://easyeda.com/sergey.romanov/dmx-splitter
Right now I am using those transformers you can see on the scheme. Those are quite bulky and I believe I do not need as much power. Is there a more elegant solution? Maybe even universal power supply so ш can connect to 110/230VAC or 12/36VDC to the same contacts.
This is my learning project, the first one ever. But later I want to use the same power supply block for my other devices. SO it is kinda important to learn what components are there nowadays for cases like this one. I am sure thee should be ready to use black box power supplies or something like this.
"...connect to 110/230VAC or 12/36VDC to the same contacts."
You can get power supplies that will handle a 90 - 240ACV 50Hz - 60Hz input and you can get supplies that will handle a 12/36V DC input but to use the same connector for the whole range would need a custom PSU design.
It would probably be simpler to have one connector with two sets of pins, one for AC mains, the other for low voltage DC and design the internal PSUs to accept a low voltage output from some sort of mains step down power supply (or supplies) or from the low voltage DC input pins. This might be better than two input supply connectors because with a single connector, you can't accidentally plug both supplies in at the same time.
For individually isolated mains to low voltage DC supplies you could look at these:
http://myrra.com/electronic-transformers/
On the other hand, having an external low voltage DC supply makes it more difficult because you then need to use separately isolated low voltage supplies (such as flyback or forward converters, which means yet more transformers, or modules) unless each DC input is itself from a separately isolated source.