A02020 — Function generator: Parameter cannot be changed

A02020 appears when a parameter setting belonging to the function generator is to be changed while the function generator is active. The function generator is controlled with p4800: as long as it reads 1, the drive refuses new values for the function generator parameters and signals this alarm instead. The alarm does not stop the drive — it only tells you that the change was not accepted until the function generator has been stopped. The manuals for the G130, G150, S120 and S150 describe it with the same wording, so one description covers all of them.

• A function generator parameter was to be changed while the function generator is active (p4800 = 1). The drive only accepts changes to these settings when the function generator is stopped (p4800 = 0).

1. Stop the function generator before parameterizing: set p4800 to 0.
2. Make the required changes to the function generator parameters (p4810, p4812, p4813, p4815 and p4820 to p4829).
3. If the function generator is still required, start it again: set p4800 to 1.

• p4800 — function generator control: set it to 0 to stop the function generator before you change any of the settings below, and back to 1 to start it again afterwards.
• p4810 (operating mode), p4812 (physical address), p4813 (physical address reference value) and p4815 (drive number) — function generator settings that can only be written while the function generator is stopped.
• p4820 (signal shape), p4821 (period duration), p4822 (pulse width), p4823 (bandwidth), p4824 (amplitude), p4825 (2nd amplitude), p4826 (offset), p4827 (ramp-up time to offset), p4828 (lower limit) and p4829 (upper limit) — the remaining function generator settings, likewise only changeable while it is stopped.

The manual's note gives the reset sequence: The alarm is reset as follows: remove the cause of this alarm. - restart the function generator. In practice: stop the function generator with p4800 = 0, make the change that was refused, then start the function generator again with p4800 = 1 — once the cause is removed and the function generator is running again, the alarm clears.