Guys, in talking with Growatt support over the last couple of days it seems that the 12KW off grid unit does not have a proper A/C charger for lithium banks. I have been testing it with a 30kw lithium bank (LG Chem cells) 560ah and I can have the unit charge the packs up to 57.8v or any other setpoint but once it reaches it, it never goes into absorb mode from what I can tell. It cuts all current and runs a maintenance charge of 50w. The 57.6v drops immediately to lets say 55v or so and while the inverter is still handling the loads, the battery voltage never increases past that point. I let it set in that state for an hour to watch and actually saw the voltage decrease .1v, Obviously with such a large bank 50w most likely will not do much for charging. I asked this question of Growatt and they confirmed that the charger is a 2 stage A/C charger that does not have an absorb stage. How can they put out a unit that cannot do this? Am I missing something here? I look forward to some input before I return this thing and swear off Growatt for any solar needs.
Thanks all and I look forward to your responses.
Thanks all and I look forward to your responses.