Hello, i'm new to this so i think i've created a problem. I'm using Mach 3 on a plasma table and everything has been working fine.  My floating Z axis would move down, trip a limit switch, reset zero and continue as it should.  I shut down for the day and came back the next day and now the z axis starts down but stops before touching, and then moves up and tries to cut way to high (this is on the exact file that cut fine the previous day). 

I'm assuming I've clicked a setting in Mach 3 but i can't figure it out, has anyone run into this and can point me in a direction.  Thankyou...Also I have a proma150 THC installed.