When my generator is running (after auto or manual start), the power it outputs is not steady and doesn't seem related to AC loads or PV Yields. Occasionally, for reasons I cannot discern, it does produce a high and steady output. When the output is steady the batteries can charge from 20 - 90% in around 2 hrs. When output is irregular (in identical PV weather conditions) batteries can take up to 4 hours to charge.
Does anyone have any advice on why this might be happening and how to fix it? My installer doesn't have a clue.
Off-grid System overview for context:
1 x Victron-EasySolar 48/5000/70-100 inverter
12 x NeOn2 LG350N1C-V5 solar panels
2 x PowerPlus ECO4840P batteries
1 x DIESEL (AIR COOLED) 7KVA 1 PHASE - Generator (Auto-start)