I currently have an existing Multiplus II GX 5kva with 20kWh, 48v batteries in grid connected ESS charging mainly solar and also a 4 hour off peak electric when the batteries are low. The issue I am starting to find is the 4 hour window is not long enough to charge the batteries (3.3kW max charge rate) so I am looking at other options on how to inject more energy into the batteries within that 4 hour window. The obvious cost effective solution would be another 48v charger timed to come on during this 4 hour period set to shut down at the same voltage bulk finishes on the Multiplus II GX.
My question is can this be done without issue or is anyone aware of any issues in doing this?
Is there a better solution? I do also have a cheap 24v 3kva inverter charger with lead acid batteries doing nothing much at the moment and I also thought about maybe using a 24v to 48v charger? Any way to connect a bus controlled 24dc-48dc charger to my existing Multiplus II GX?