During the boot-up sequence, the drive may briefly display a firmware version or software ID, which could look like "2563".
A municipal water utility operated a Danfoss VLT HVAC FC 102 controlling a 75 HP pump. After a lightning storm nearby, the drive displayed Alarm 2563 every 2–6 hours. Danfoss Vlt Error Code 2563
Contact Danfoss Global Service if:
Initialization to Default Settings | VLT® HVAC Drive FC 102 During the boot-up sequence, the drive may briefly