The panner node is a constant input for your texture sample. That particular is used to continuously pan an X or Y value. You can set up an event, for your purposes, that allows you to click a button and you can draw this material. There a number of ways to do this. One way is to draw a Widget, or you can spawn a static mesh with the material applied to it.
With a panner node you are limited to frequency, speed, time of how quickly you want your texture to pan.