I’m looking to add extra charge power to DESS and switch it automatically.
Setup:
- 40A single phase 230Vac
- Multiplus II 5000 GX running DESS in Trade mode, no solar
- One 43kWh Li-Ion batterybank, allowing 0,25C upto 0,50C charging (10-20kW)
- Smartshunt on battery
- Multiple 3kW high efficiency chargers, can-bus protocol known, pull-to ground enable available
- All AC loads on output feeding small home, 200 to 400 kWh monthly, weather and heating to most varying conditions and loads.
With grid supply available upto 9400W, I’d like to boost charging upto 9000W by enabling three(3) 3kW high efficiency chargers, that are connected to AC OUT2 of the MP. This will allow for the MP II to automatically reduce it’s own charge current not to exceed the 40A AC IN1 limit.
My question concerns the use of (relais) assistents to switch on (one or more) boost chargers when prices are low. I found some settings in VE.Config that would use the VE.Bus signals to determine when to switch on or off some relay but to my best knowledge that won’t work because the VE.Bus is practically always in BULK mode, with DESS charge or discharge operation being controlled by the positive/negative difference between the measurred SoC (smartshunt) and the SoC target provided and regularly updated by the DESS assistent on the GX
Could anybody point me to a usable scheme to get this implemented in such a way that the boost chargers will only be enabled when DESS is requesting more charge power then (a certain percentage of) the maximum charge current (70A) of the MP II? And visa versa stops when requesting less.