Help with a research proyect!

I have 30 cables on one side

and 3 on another
example:

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until 30...

I need to build a component that will connect the 30 to the 3 in a particular way:
Say these are the first 12 of the 30:
1
2
3
4
5
6
7
8
9
10
11
12

and 3 cables ABC

The component needs to connect: 123 to ABC
then..
456 to ABC
then
789 to ABC

And so on.
The connection needs to last 5 second to each trio before switching to the next:

example:
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5 sec pause

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5 sec pause

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..
Any Thoughts..?
how to build this component.
Im not an electronics expert,
rather a physician... working on a research proyect.

This component you're reffering here is called analog mux. It works just that way.

Just search for "analog mux" on the web, an make sure you find one that has as many inputs as you need. Otherwise you must go for a two-input mux and cascade them.

You need three separate muxes with at least 10 inputs each (and one output each). If you can get muxes with fewer inputs, then you must cascade them and make a logic circuit to control them properly.

The first question that comes to my mind is what you want to connect the cables for? Like voltage, current and speed of the signals going through the cables.
The second is: Will each line only connect to one of the 3 on the other side. Like 1A, 2B, 3C, 4A, 5B and so on. and not like 1B, 2A, 5C ?