A07091 — Drive: determined current controller dynamic response invalid

A07091 is issued when the current-controller measurement belonging to one button tuning has finished with a poor result. One button tuning is activated with p5300 = 1, and the drive then measures the current controller after the pulses have been enabled. If the evaluation finds that the current control loop was not appropriately set, the drive raises this alarm and writes an alarm value to r2124 that tells whether the dynamic response came out too low or the current controller came out unstable. PRBS — Pseudo Random Binary Signal (binary noise) — is the test signal of this measurement; its amplitude is set in p5296, and an amplitude set too high is one of the possible triggers.

• The current controller is set incorrectly.
• The PRBS amplitude in p5296 is set too high.

1. Read the alarm value in r2124 (interpret hexadecimal) to see whether the dynamic response was evaluated as too low or the current controller as unstable.
2. Repeat the measurement with a smaller excitation amplitude: reduce p5296 and run one button tuning again with p5300 = 1.
3. If required, adapt the current controller proportional gain in p1715.

The drive stores an alarm value for this message in r2124; the manual says to interpret it hexadecimal. The value distinguishes the two evaluation findings:

• 1: Dynamic response too low.
• 2: Current controller unstable.

• p5300 (Autotuning selection): set to 1 to activate one button tuning; this starts the current controller measurement after the pulses have been enabled. Activate it again to repeat the measurement.
• p5296 (FFT tuning PRBS amplitude): the excitation amplitude of the PRBS test signal — reduce it when the measurement has to be repeated after this alarm.
• r2124 (Alarm value): holds this alarm's alarm value, read hexadecimal — 1 dynamic response too low, 2 current controller unstable.
• p1715 (Force controller P gain): the current controller proportional gain, which you adapt if required when the evaluation fails.

The manuals specify no acknowledgement procedure for this alarm. It is resolved through the remedy itself: adjust p5296 and/or p1715 as required and repeat the measurement by activating one button tuning again (p5300 = 1). Once an evaluation finds the current control loop appropriately set, the condition that raises A07091 is gone.