>>2940114
Ethernet cable is not rated at 10A, and depending on your supplier it may not be rated at 250VAC. You can likely use it for your purpose, because even sellotape will resist 250VAC and you won't be drawing anywhere near 10A. It's up to you whether you want to disregard the regulations on this matter. But I'd look at getting some less delicate wire that is 10A idiot-proof, like some shielded automotive cable. If you look in the spec sheet a lot of automotive cabling is rated for use with 250VAC.

As for noise immunity, you've got both magnetic and electric field noise to contend with. If it's a class-1 grounded appliance, then you can basically disregard electric field noise in the appliance as the chassis will block it. Still might be an issue if you happen to have high-impedance signals going near the power cable, this is where you'd want to have grounded shielding around the outside of the power cable. Magnetic noise isn't as easy to mitigate though it isn't usually as impactful, the best method is to twist the power wires together tightly so the magnetic loop areas cancel out in as near a field as possible. Normal mains cable twists every 10-30cm or so, ethernet cable twists every 1-3cm or so, hence its better suitability for mitigating magnetic noise. Some methods of using multiple twisted pairs twisting in opposite directions can be even better than just one. But you want the ground wire to be capable of shunting as much current as the live wire in event of a ground fault without a GFCI, so I'm unsure what cable mapping you'd use, I'd want to get shielded twisted pair cable with a drain wire at least. It might also be worth looking at differential (XLR) audio cable, it's often twisted for these same reasons, picrel.