I have a 1997 VM16 that did the same thing. Smithereened an Interapid indicator. Our local serviceman couldn't find the problem, and said "these intermittent things are hard to diagnose". An EE friend said "check all the neutral connections, you're getting a transient somewhere". I tightened every connection I could find, including the X axis connector on the computer box, which was loose and had nearly parted company. I also replaced the X axis servo motor and encoder, which was full of coolant, and put a decent stainless steel watertight strain relief on it. The last act was to place a label on the control panel that says: Do Not Trust Me. I am the only one who operates this machine (one man shop), and S.O.P. is to turn the spindle speed down to zero when it absolutely, positively, mustn't turn on (such as when using a new Interapid indicator). The problem hasn't reoccured since the repairs, but I still treat it like a loaded gun. |