Troubleshooting Fanuc Alarm 366: SV Pulse Miss (Built-in) The Fanuc Alarm 366 (often displayed as SV0366) is a critical servo alarm indicating a "Pulse Miss" in the motor's built-in pulse coder. This occurs when the digital servo software detects that the encoder is losing data integrity—essentially "missing" pulses that are necessary to track the motor's exact position. What Causes Alarm 366?
While the motor is running (if possible), check for excessive heat or vibration in the motor housing, which could indicate failing bearings impacting the encoder. Test the Motor/Encoder: fanuc 366 alarm
Prevent recurrence with this monthly checklist: Troubleshooting Fanuc Alarm 366: SV Pulse Miss (Built-in)
Troubleshooting Steps: