ALARM 218

Axis Move Misoperation / Chucking Type Not Selected

Servo lag — motor cannot position the axis (almost always paired with Alarm 2 'Servo lag excess'). On older DC-drive Mazaks the cause is brushes worn out, br...

Controls: T-3, T-Plus, T-32, T-32B
Machine series: Slant Turn, Quick Turn, SQT

Causes

Servo lag — motor cannot position the axis (almost always paired with Alarm 2 'Servo lag excess'). On older DC-drive Mazaks the cause is brushes worn out, brushes stuck, commutator burned, or the flexible coupling between servo motor and ballscrew has broken.
- benganbollforum
  The coupling did fix the problem
On SQT machines the 218 wording is 'Chucking type not selected' — the control does not know whether the chuck is set for ID or OD work, or the open/close proxy switches did not make after the last switch change.
- TeachMePleaseforum
  But I do know most lathes have a parameter to select either ID or OD chucking. Seems to me, this paramater is not set properly for your machine.

How to clear it

1
For servo-lag flavor on T-3: pull the flexible coupling between servo motor and ballscrew; if cracked/broken, replace it. Then pull and inspect the four brushes (under threaded plugs on the tach end of each servo motor). Also check the timing belt tension between motor and screw and the pulley retaining nut on the ballscrew end.
- Philabusterforum
  FYI, there are 4 brushes to each servo motor.
2
For chucking-type flavor on SQT: verify the ID/OD chucking selection in the chuck data page, then exercise the chuck open/close foot pedal to confirm both proximity switches make.
- wms111forum
  Check to see that it is making the proximity switches for the open and close.

Additional notes

Alarm 218 means different things on different controls — on T-3 it is an axis-move/servo-lag alarm; on T-32 the same code displays as 'Chucking type not selected'. Always confirm the control version and the on-screen text before applying a fix.

Confidence: high · Two distinct flavors of Alarm 218 documented across two PM threads with confirmed operator resolutions in each.

First sourced: 5/21/2026