Fanuc Alarm 21: ILLEGAL PLANE AXIS COMMANDED
Fanus Control Model: 16/18/21, 16i/18i/21i
Alarm Description
An axis not included in the selected plane (by using G17, G18, G19) was commanded in circular interpolation. Modify the program.
Help the CNC Community: How Did You Fix It?
If you have encountered this Fanuc 21 ILLEGAL PLANE AXIS COMMANDED error code before or know a proven troubleshooting step to resolve it, please share your solution in the comments below