If you have a legacy Printrbot or just have an aversion to induction sensors, see the steps below to use a good old-fashioned end stop for the Z axis on your Rev F5 Printrboard. NOTE: F6 Printrboard is not compatible with a Z end stop. You must upgrade to an Auto-Leveling Probe.
1.) Move your “Z-VSel” jumper to select “5V”.
2.) Using a pick or similar tool, remove the black wire from the end-stop housing and re-insert the wire into the center slot.
3.) Using a soldering iron, remove the “Yellow” wire, and re-solder it to the center pin of the end-stop.