Hi. I'm having an issue with Quattro and Multiplus inverters continuing to send a small amount of current to the batteries even though the batteries are at 100% and the charge current is supposed to be 0. This only happens when connected to a genset, the systems work properly when connected to the grid. I have tried the assistant that is supposed to turn off the charger when charge current is 0 but this has no effect. Any help would be much appreciated.
To repeat the most common mantra: you're going to give a whole lot more detail about the setup and all the settings, unless you can loan us a crystal ball - the batteries are flat in the current one :)
Thanks for the quick reply. I am an installer and this is a common problem for me that I have been trying to solve for a while so its not isolated to a single system. I can give you the details of one such system. 10kVA Quattro with 4 X US3000B Pylontech batteries and a 150/100 Smartsolar MPPT with 18 X 330W panels. AC input 1 is connected to the grid and AC input 2 is connected to a Tech Africa 11kVA Genset. The system also has a CCGX. When the genset is running and the batteries have reached 100%, the battery voltage creeps up above 53V (when connected to grid it never goes above 52.5V) and the MPPT shuts down with Error code: #38 - Input shutdown due to battery over-voltage.
Let me know if you need any further details.
Is there a particular reason why the mppt and the victron are not set the same? And to recommended voltages on mppt?
Is this happening when some solar is available and the genny is running?
I did have a set of batteries (not Pylons) do this on grid at night, but found it was a cell balancing issue that was causing this, had to have the battery repaired.
FYI the battery bank at 4x US3000 is a bit undersized for a 10kva. Needs two more units to be most correct for nominal running.
The problem is the same if not worse when solar is available.
The pylontechs tend to have a cell balancing issue when they are new but it resolves itself after a few days.
I know that 4 batteries is a bit light for a 10kVA but this inverter is oversized, an 8kVA would easily have handled and the clients' nighttime loads are minimal.
52v abs and 51v float.
The minimum batteries are sized for the inverter and solar, not for loads. Unless the autonomy requires a larger bank that should be the minimum in the setup.
Lowering the voltages on the mppt will make the problem worse because error 38 occurs when the voltage of the battery exceeds the settings of the mppt. For Pylontech, Victron overrides the requested voltage from the battery (float 53.2) and sits at around 52.5, which is above the absorption setting on the mppt. The issue with the mppt is a symptom of the main issue which is that the inverter doesn't stop charging the battery when connected to a generator (mainly cheaper generators).
Regarding the battery and inverter sizes, 8kVA was out of stock.
Did you set the AC IN 2 to "generator" in the CCGX -> Settings -> System-Setup?
Try to use a different setting there.
