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Navigate to Diagnostic > Machine Data > $MA_SAFE_VELO_LIMIT in the NCK parameter menu for the affected axis.

Compare the current value against the axis maximum velocity specification (typically MD $MA_MAX_VELO or physical machine limits). The safe velocity limit should be at or above the highest commanded velocity in your NC programs.

If the value is too low, increase MD $MA_SAFE_VELO_LIMIT to an appropriate value and save. Perform a machine warm restart (Control Panel > Restart > Warm) to apply changes.

Ensure the new limit does not exceed mechanical axis capabilities or servo loop stability margins.

Test axis movement with a simple G01 move at moderate feedrate to confirm alarm does not recur.

Verify SBH/SG configuration is active: Navigate to Drives > Safety > SBH/SG Settings in the NCK menu or check SD $SD_SAFE_BH_ENABLE and related safety MDs.

Check MD SAFE_ENC_FREQ_LIMIT (typically 10-50 kHz depending on encoder resolution and safety hardware). Calculate current encoder frequency: (Axis Velocity in mm/min) × (Encoder Pulses per mm) / 60,000 = Frequency in kHz.

If encoder frequency exceeds the limit, either reduce commanded axis velocity in NC program or increase encoder resolution/reduce machine pitch to lower pulse-per-mm ratio. Alternatively, upgrade to a dual-encoder system (2-encoder configuration) which is not subject to this limitation.

Do not simply increase SAFE_ENC_FREQ_LIMIT beyond hardware capability; this defeats safety protection.

After adjustments, perform a full system test including SBH trigger verification to ensure safety chain integrity remains intact.

Monitor actual axis velocity during alarm occurrence using Diagnostics > Oscilloscope or Trace function. Plot the actual velocity (from encoder feedback) against the commanded velocity setpoint to identify overshoot patterns.

Review servo tuning parameters: Access Machine Data > Servo > Axis [X/Y/Z] and check MD $MA_GAIN_P (proportional gain) and $MA_GAIN_D (derivative/damping). If P-gain is too high or D-damping too low, reduce P by 10-20% or increase D gain.

Check acceleration/deceleration ramps: Verify MD $MA_ACCEL and $MA_DECEL are appropriate for the axis mass and servo bandwidth. If overshoot occurs during rapid acceleration, reduce $MA_ACCEL incrementally and retest.

Excessive servo tuning can cause oscillation; make small parameter changes (5-10%) and test between each change.

After tuning adjustments, perform a warm restart and run a test cycle with velocity monitoring enabled to confirm overshoot is eliminated and alarm does not recur.