whats it do ?
does it go in the home direction and slow down? then alarm out with hard OT?
does it not get to slow down and just alarms out with a soft over travel?
if soft over travel then open up that 1320 parameter
if it slows down then hard overtravel then you want to find "Grid shift" parameter and start by cutting it in half.
if that does it then you want to get it right by useing a known height block on the table.
bringing down the head till block just slides under. then write down machine position for Z and send machine back home. do the math between the two machine positions and adjust the "Grid shift" parameter as needed to give you the factory stated travel between table and spindle nose.