I can't say for sure without reading the article you did, but I do know about typical signal wires.
Single conductor, low voltage DC signal wires are prone to picking up electrical noise that can influence the signal. One way this can happen is by their being routed too closely to AC power wires. What happens is there is an EM field produced by the AC circuit and that field induces a current in the DC wire.
By twisting the wires together along their route, any EM field to which the wires are subjected will induce equal and opposite currents in the two wires. This, in turn, negates the effect.
I imagine this is the same for the stepper but I am not sure.
Steve |