Bob,
On my VFD controlled lathe, the JOG button acts as an ON, but turns
OFF when released.
Is it useful, yes. I use it a lot when I use the change gears to
adjust the feed rate. The right handle never wants to engage without
a little chuck rotation.

Note, on my lathe the physical JOG button is wired the same as the run
switch. It is not wired to terminals called jog, and the VFD has no
idea if it's a RUN or JOG.
Dave


On Jan 28, 7:45 am, Bob Engelhardt wrote:
How does this work (the manual isn't clear)? Is it useful?

Bob