Ok , I've to explain you again:
Our machine was worked for long time with any problem.
But 3 days a go this problem was happened:
When the cnc machine complete the hacking work, automatically traveling to home (the gcode line number is final line & the gcode traveling position is x=0/y=0/z=0).
Hence, x & y axes travleing to "0" position but z axes crossing the "0" position and hits the table.for example the position of z at this time is "-50" but It should be "0" position.
And finally the counter display of mach3 showing{ x = 0,y = 0,z = -50}!!