231-9520

Access machine parameters

Press MOD key, select 'Machine Parameters' from setup menu, navigate to spindle/drive configuration section.

Use parameter search function (GOTO) to quickly locate vCtrlTimeSwitchOff

Locate vCtrlTimeSwitchOff parameter

Find parameter vCtrlTimeSwitchOff in the drive/spindle parameter group, note current value of 0.

Document original parameter values before making changes

Configure appropriate braking time

Set vCtrlTimeSwitchOff to minimum 500ms or manufacturer's recommended braking time for your spindle motor.

Consult machine builder documentation for optimal braking time values

Validate and restart control

Save parameters, perform control restart, and verify alarm clears during next spindle operation.

Test spindle braking behavior at low speeds first

Check spindle motor specifications

Review spindle motor datasheet for rotor inertia, maximum speed, and recommended electrical braking time.

Higher inertia spindles require proportionally longer braking times

Calculate minimum braking time

Use formula: Minimum time = (Spindle inertia × Max RPM) / (Braking torque × 9550), add 20% safety margin.

Insufficient braking time can cause spindle overshoot and potential damage

Adjust vCtrlTimeSwitchOff parameter

In machine parameters, increase vCtrlTimeSwitchOff to calculated minimum value plus safety margin.

Start with conservative values and reduce gradually if needed

Test braking performance

Run spindle at various speeds, monitor braking behavior and verify no alarm recurrence.

Monitor for excessive braking times that may impact cycle time

Check parameter backup status

Access MOD menu, select 'Data Management', check if recent parameter backup exists and compare timestamps.

Always maintain current parameter backups before making changes

Restore from known good backup

If valid backup exists, restore machine parameters from backup file created before alarm occurrence.

Verify backup compatibility with current TNC software version

Manually reconfigure if no backup

Contact machine builder for original parameter settings or use commissioning documentation to restore vCtrlTimeSwitchOff.

Create new parameter backup immediately after successful restoration

Implement parameter protection

Set appropriate user access levels to prevent unauthorized parameter modifications in future.

Ensure maintenance personnel retain necessary access for legitimate adjustments

Check drive amplifier parameters

Access drive-specific parameters in TNC, verify braking resistor and regenerative braking settings match physical hardware.

Use drive diagnostic functions to verify actual vs. configured braking capacity

Verify braking resistor operation

Check braking resistor connections, resistance values, and thermal protection status in drive diagnostics.

Faulty braking resistors can cause inadequate braking performance

Synchronize TNC and drive parameters

Adjust vCtrlTimeSwitchOff to match actual drive braking capability or reconfigure drive for faster braking.

Consult drive manufacturer's commissioning software for optimal braking setup