Danfoss · VLT 2800 Variable Speed Drive
This alarm indicates that the drive has entered a Trip-Locked state, meaning it cannot be reset by simply pressing the [STOP/RESET] key. This usually occurs after a severe fault to ensure safety and require manual intervention.
Click steps to track your progress.
Record the specific fault code that led to the Triplock state (often displayed alongside or prior to Triplock).
Completely remove all AC input power to the drive. Wait for the DC bus voltage to discharge to a safe level (typically <50VDC) using a multimeter.
Restore AC input power to the drive. This power cycle typically clears a Triplock state if the underlying fault has been resolved and is not persistent.
If the Triplock persists, access the drive's internal fault history log via the keypad or communication software to identify the root cause fault.
Check all safety chain inputs (e.g., STO terminals) to ensure they are de-energized and then re-energized correctly according to the safety circuit design.
If the previous steps fail, contact technical support for potential advanced diagnostics, firmware re-initialization, or hardware replacement procedures.