I have an early 90's Fadal VMC40. I have been having issue with Z axis running rough moving up. When I send it home the Z goes all the way up and the X, Y doesn't move.
It gives me an emergency message. I jog the machine to home position then CS, it did not stay at home position.
I had to shut off and restart it seems to be ok.
Do you think my Z amplifier card is defective? Which card is the Z?
be sure you are sending it home without any offsets.
try G0G28H0Z0. also if you jog it close to the cold start positions, did you do a setcs?
that resets the cold start position.
i really doubt that the card is bad.
i have seen people mess the z cold start position very often,
be thankful that it did not head towards the table, the night guy did that to me more than once.
check or adjust the encoder of the z axis (is on the top of the machine)
also change the position of the amplifier (the z is on the down position)
good luck