A07976 — Drive: Fine encoder calibration activated

A07976 is the alarm the drive issues while a fine encoder calibration is running. It is a progress signal rather than a fault message: the drive writes the phase the calibration has reached into the alarm value, which is read as a decimal number, and the message value carries a parameter reference. The calibration belongs to the parameter tuning function selected in p1905 and passes through activation, the rotating measurement and the calculation of the values; the alarm accompanies it throughout and signals an interruption with alarm values of its own. The manual gives the alarm value the following meanings:

• The alarm appears because a fine encoder calibration has been activated (parameter tuning, p1905); it reports which phase of that calibration is running and is not a malfunction report.
• Two alarm values do report that the rotating measurement was interrupted: because the speed was too low (value 10) or because the torque was too high (value 12).

1. Read the alarm value and match it against the phase list to see where the calibration stands.
2. During the rotating measurement, set the setpoint speed to more than 40 % of the rated motor speed, as the phase 2 entry requires.
3. If the alarm value is 10, increase the speed — the rotating measurement was interrupted because the speed was too low.
4. If the alarm value is 12, run the drive without load — the rotating measurement was interrupted because the torque was too high.
5. When the rotating measurement has completed successfully (alarm value 4), initiate pulse inhibit so that the drive accepts the determined values.

• 1 — Fine encoder calibration active.
• 2 — Rotating measurement started (set the setpoint speed > 40 % rated motor speed).
• 3 — Rotating measurement lies within the speed and torque range.
• 4 — Rotating measurement successful: pulse inhibit can be initiated to accept the values.
• 5 — Fine encoder calibration is calculated.
• 10 — Speed too low, rotating measurement interrupted.
• 12 — Torque too high, rotating measurement interrupted.

• p1905 — Parameter tuning selection: the setting with which the tuning run is selected whose fine encoder calibration the alarm accompanies; the manual cross-references this parameter for the alarm.

The manual describes no reset procedure for this alarm: it moves through the phases together with the running calibration. If the rotating measurement was interrupted (alarm value 10 or 12), the measurement is repeated once the speed has been raised or the drive has been taken to a no-load condition.