I am posting on behalf of a user on another forum that was unable to sign up due to captcha issues (edited and paraphrased):
Battery depleted overnight.
In the morning when the solar chargers started up, the Multiplus II tried to restart a few times and then shut down. likely because the heat pump remembered its last running state and would also attempt to restart, dragging the battery pack back down.
The MPII remained off for a little over nine hours. During this time, the MPPT fully charged the battery. In the evening, the cutoff switch to the heat pump was pulled. The inverter instantly restarted without having to manually reset it.
Does anyone know why the inverter would do that rather than require a manual reset? I am glad that it did, I am just curious why. It’s as if the inverter was monitoring what loads were attached to it, recognized the “problem load” had been removed, and then restarted.
