Hi all, just a quick question from a newby, is it possible to switch between closed loop and open loop via macro in mach turn? The closed loop is nice in the sense that it boosts the vfd more when machining larger diameters or drilling with larger drills, problem with closed loop is that you cannot override the spindle speed via pot, only on the screen with percentage spindle speed. So the main use will be to only recall the closed loop for a operation and then cancell after that particular operation is done unless if there is another way.

Dont think so.
You can use a pot to Mach to override spindle but it requires an analogue input, the cheapest way would probably be with a PoKeys. If you have spare inputs then you could have three buttons, one to increase, one decrease and another reset, you could then have a brain look at the inputs and step the spindle speed up or down accordingly.
Hood