The traveling spiral is created by stacking a sequence of rings along a main path, with each ring rotated on the axis of the center normal slightly more than the previous one. Instead of leaving them as separate circles, a single continuous thread is snapped to their vertices, forcing the line to wrap around into a coiled spring due to the incremental rotation with an Accumulate Field solution. To animate the shape, a sliding focal point travels along the path, scaling the spring down to zero everywhere except in its immediate vicinity, which creates the illusion of a short, localized spiral traveling down the wire.

Simply take your curve (spline), apply the GeoNodes setup and away you go ! 

The parameters of the effect are completely customizable.