in the application note "Integrating with SolarEdge" it is written :"Note: APS mode is mandatory for systems requiring both zero feed-in in on-grid mode and frequency shifting in off-grid mode."
I can confirm that for SetApp inverter with firmware CPU 4.9.33, (DSP1 1.0.1036, DSP2 2.0.910) and country settings Spain & Italy when in APS-mode the settings in corresponding P(f) are being ignored, no power reduction on rising frequency occurs.
For country setting Spain: Power Control-->Active Power: P(f) is not available
Frequency shifting in off - grid mode is desired and I get a P(f) reduction when using country "Italy" according to the defined ramp P(f) in "Active Power". However there is a hysteretic lock, frequency needs to fall back to 50Hz again + some hold time until a new reduction cycle is started. (A wakeup gradient to improve system stability is defined though: (200ms))
@fjlacock is this hysteretic behaviour of P(f) also the case when in APS -mode? Apart from the extended trip values in APS mode, is there a difference between P(f) in that mode and “P(f)” in “Active Power” + default country mode?