I have a grid parallel setup with ESS working perfectly, apart from when there is high grid load during a scheduled charging window.
Setup is as follows:
- Multiplus-II (48/3000-35-32) inverter AC In connected to Grid, no connections to AC outs, with AC coupled PV on input side. CT clamp on meter tail connected to Multiplus-II for grid consumption monitoring.
- Cerbo GX setup with ESS (With Batterylife Optimisation on) with scheduled charging setup to take advantage on my low rate overnight time of use tariff.
- Batteries are 3 x Pylontech US2000C
Scheduled charging works fine until my EV charger kicks in (same window) and suddenly grid load is ~9.5kW with charger, baseload and EV 7.2kW charger, the charging then stops and the batteries start to discharge even though this is a scheduled charging window.
Is this expected behaviour? Surely the inverter should realise this is not current following through the inverter itself, just the AC side of the setup?
My idea for a 'quick' fix is to relocate the CT to my distribution board, as my EV charger is supplied from a separate DB directly from a distribution bus before the main DB, however the cables are tricky to access so keen to know if this will work before making access.
Any advice appreciated!