1A0-00E6

Identify the failing PLANE command

Locate the exact NC block triggering the alarm. Note the PLANE function type (SPATIAL/VECTOR/PROJECTED) and all parameter values (SPA/SPB/SPO or X/Y/Z vectors).

Use SINGLE BLOCK mode and position cursor at PLANE command - alarm will trigger at block start before motion begins.

Check rotary axis software limits

Access machine parameters MP3602.x (axis A), MP3603.x (axis B), MP3604.x (axis C). Compare software limits against required rotary positions for the programmed orientation.

Calculate expected rotary positions manually or use Test Run simulation with 'show axis positions' to see calculated A/B/C values before alarm.

Verify kinematic model configuration

Check MP7500.0 (kinematics type), MP7502.x (rotary axis assignment), MP7510.x (geometry distances). Ensure configuration matches actual machine head/table design.

Incorrect MP7500 series parameters can cause permanent orientation calculation errors - document original values before changes.

Modify PLANE orientation angles

If orientation is at or near ±90° on swivel axis, try alternative orientation angles (use SPA +/- adjustment or modify CAM post-processor solution preference). Test with SEQ +/- increments.

For head/head kinematics, B-axis values near ±90° create singularities - stay within ±85° if possible.

Verify TCPM mode and status

Check current modal state for M128/M138 in Program Run Overview. Confirm FUNCTION TCPM mode matches intended operation (F TCPM or F TCPM AXIS).

Press 'Show Positions' softkey during Program Run - TCPM active indicator shows in position display.

Check MP7502 rotary axis assignments

Verify MP7502.0 (1st rotary axis), MP7502.1 (2nd rotary axis) correctly identify which machine axes (3=A, 4=B, 5=C) are rotary. Incorrect assignment prevents valid TCPM calculations.

MP7502 changes require control restart and may affect all 5-axis programs - perform during scheduled downtime.

Validate tool length compensation

Ensure active tool has correct length values in Tool Table (R and R2 for tilt-head machines). Invalid tool length causes incorrect TCPM position calculations.

Test with T0 (zero tool) to eliminate tool length as variable - if alarm clears, tool data is suspect.

Disable TCPM temporarily for testing

Insert M129 (TCPM off) before problematic PLANE command to test if orientation is achievable without tool center point management. If successful, TCPM configuration is the issue.

Use Programmable M function with M129 in subprogram for quick enable/disable testing without main program edits.

Inspect orientation vector values

Examine I, J, K values in failing block. Calculate vector length: √(I²+J²+K²) must be non-zero. Check for I0 J0 K0 which is undefined orientation.

Heidenhain normalizes vectors internally, but zero-length vectors (I0 J0 K0) always cause this alarm.

Test with simplified orientation

Replace complex orientation vector with simple vertical tool (I0 J0 K-1) or use PLANE RESET to return to standard machining plane. If alarm clears, original vector was invalid.

Use MDI mode: PLANE RESET followed by L X+0 Y+0 Z+0 I0 J0 K-1 to test basic orientation calculation.

Check CAM post-processor output

Review post-processor for proper vector calculation, especially at surface boundaries or blend transitions. Look for discontinuities in I/J/K values between consecutive blocks.

Search NC program for sudden I/J/K changes >30° per block - these often indicate post-processor surface normal calculation errors.