024

Locate the alarm line number displayed on the CNC screen and find that block in your program.

Check if G17, G18, or G19 appears before the arc command (G02/G03) in the program initialization or earlier in the sequence.

Verify the plane selection matches your intended arc motion: G17 for arcs in XY plane, G18 for arcs in ZX plane, G19 for arcs in YZ plane.

Add or correct the plane selection command in the program header or immediately before the arc block, then reset and restart the program.

Ensure workpiece setup and tool orientation are compatible with the selected plane to avoid crashes.

Review the alarmed G02/G03 block and note the start position (current tool location), endpoint coordinates (X, Y, Z), and arc parameters (R or I/J/K values).

Calculate the distance from arc center to both start and end points - they must be equal. For R format, verify the distance between start and end points is not greater than 2×R.

Check for decimal point errors, missing values, or transposed digits in the arc command coordinates that would make the geometry invalid.

Correct the arc parameters or endpoint coordinates to create valid geometry, verify using CAM software backplot if available, then test the corrected program.

Use incremental arc center (I/J/K) format for more precise control on critical radii to avoid tolerance issues.

Search backward from the alarm block for any G17/G18/G19 plane change commands between program start and the alarmed arc.

Check if a drilling or tapping canned cycle (G81-G89) is active without proper cancellation (G80) before the arc command - canned cycles lock the plane.

Verify that all subroutine calls maintain consistent plane selection or explicitly set the required plane at the subroutine start.

Different subroutines may have different plane requirements - always explicitly declare plane selection at the beginning of each subroutine.

Cancel any active canned cycles with G80, ensure plane selection is consistent throughout the operation, or restructure the program to complete all operations in one plane before switching.