The Machine is a Niigata SPN50 with a 16-M Fanuc Control, and today the operator was running a piece that we do often. At is second piece, suddenly the Z axes crashed bruttaly in the piece. Like if he loose is position for a moment. Someone here told me that about 10 years ago, a problem like this happens and he think thats like if the program would have skip some lines and that causes the crash... Pretty strange. The program was not running in drip feed, and we recheck the program in the controller and everything is ok. The only error that we have is Z Excess (overload)... could it be the encoder? We redo the same program in slowmotion and everything was ok... All the position are good in the 5 Axes. The H1 for the tool was at the good dimension (before the crash)

So my question is, did someone here have an idea or have already a problem like this before? Or any suggestion. Is there is something i can try with the controller to test it?

As i said before, some guys here think that sometimes the controller skip some line in the programs? alerady see that?

We restart the machine after a mechanical check, and position check, etc... but i want to solve that problem.... We scrap a tool, a jig, and the vise on the block! And the operator began to be afraid of his machine.




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