Problem- Fanuc 10t Alarm OT116

[golijoe]

The alarm is OT116 and the description of it is
OT 116 Disconnection Pulse Coder Bad Pulse Coder. Broken Cable.
How can you tell if it’s X or Z

[GPena]

This alarm is usually a broken cable, check both, z axis is most common to fail so, check first the z axis cable.

GP.

[golijoe]

We do a lot of broaching on this machine so the spindle is not rotating but when I talked to the operator and he said that if he rotates the chuck to a certain position the alarm will go away. Would there be any correlation between the 2?

[cnc2149]

This alarm refers to a lack of spindle 'position' feedback (not X or Z axis servo feedback). Most lathes have an encoder on the spindle so you should look at it. Unplugging the spindle feedback cable on a working machine would produce the same alarm. It does not relate to the velocity feedback, so that is why the spindle may still be able to operate in M3/M4.

[GPena]

Check the spindle encoder cable, it seems that it is broken.

[GPena]

Oh, you got that from cnc2149...

[golijoe]

Thanks, that helped and it looks like we found the problem.