Using a twisted pair-wiring for sensors or other data that can be susceptible to noise is something I commonly see recommended, but whenever I try to do additional reading to understand the trade-offs, benefits, limitations, appropriate-use-cases, etc, I just end up more confused than before.
Some places seem to say its not actually helpful, other places say its helpful in some cases but not others, other places seem to suggest that its only helpful if one of the pairs is grounded, others say unless you're looking at a balanced signal its not helpful.
I have an intuitive sense of how I think it works, but I've been wrong before, so I'd like to clear it up if I can. To allay this confusion in practice, I've just kinda taken to doing as many things as I can as twisted pair, if for no other reason than it makes the wiring much tidier in projects.
So I'm left with a few (probably silly) questions of when to use, when not, and how to use.
Do you use twisted pair for DC power-supply lines? In that case would it be VCC and GND twisted
around each other, or two VCC lines twisted around each other plus two GND lines twisted around each
When using twisted pair for a sensor does it matter whether the data line is tied high or low, and does
that affect whether the second wire in the twisted pair is GND?
Would using a twisted pair, or twisted bundle be appropriate for multi-channel lines like RGB LED wire?
If so, how would that look? Would each data line need to be its own twisted pair with one of the wires
being the data-line, and the other wire being ground (resulting in a total of 4 twisted pairs for the 3
channels plus VCC)?
Is there ever a benefit (other than tidiness) to twist-up more than 2 wires together?
Are there instances where you would NOT want to use a twisted-pair arrangement for functional
purposes (like transmitting certain types of data or data-speeds)?