Fanuc alarm PS0021: ILLEGAL PLANE SELECT
PS alarm (program/operation) · Fanuc 0i-D
What it means
The plane selection commands G17/G18/G19 are in error, e.g. parallel axes were specified for the same plane, or an axis inappropriate for the selected plane (such as circular interpolation axes) was commanded.
Likely causes
- Duplicate or conflicting axes assigned to one plane
- Axis addressed that does not belong to the active plane
- Plane parameters misconfigured
Need the part urgently?
Send us alarm PS0021 with your machine details — typical RFQ turnaround is 24–48h.