We have been noticing strange behavior from a SmartSolar MPPT 100/50 charge controller and its system partner Cerbo GX.
These two devices are part of a small portable system which provides constant power to a small load in an unmanned and remote area. It is for this reason that we can't easily reboot the entire system. We have only been able to reboot the Cerbo GX through VRM.
The system also consists of a small Phoenix inverter, a shunt, a 12V Lithium battery, relevant breakers on each device, and two PV modules in series.
The system was working fine for several weeks until we began to notice two strange behaviors during bulk and float stages. The absorption stage has been normal.
During bulk charging in the morning hours, the MPPT output voltage and current are sometimes sporadic and contain much ripple. The voltage and current follow one another during this ripple. Bulk stage plots attached below.
Ripple becomes more aggressive during float stage as the day progresses. The ripple during float stage is accompanied with re-bulk attempts even though the float voltage never drops below the rebulk voltage for the required 1 minute to actually trigger an expected rebulk stage. Image of float stage ripple and unwarranted rebulk attempts attached below.
Also, during times of high ripple, all data seems to drop for periods ranging from minutes to hours.
Once the MPPT turns off after sunset, the system does not exhibit any problems.
We have switched over from Magnum and Outback and have been building small and large systems with Victron exclusively for a year now. We have not seen this before.
I have also attached a plot of this MPPT prior to the problem to show normal operation.
UPDATE Aug 1:
The system performance has been getting worse. I have updated the Cerbo GX firmware since it is the only one I can update remotely, and I have attempted several reboots. No success.
The VRM dashboard and Remote Console Dashboard have been frozen and do not display actual real time information. Screenshots attached. Upon exploring the MPPT, shunt, and inverter through the remote console, each of those devices seem fine. The dashboards are just frozen.
Rough Bulk Stage.pngRough Bulk 2.pngFloat Stage Ripple.pngRipple Rebulk Close Up.pngUnwarranted Rebulk Attempts.pngNormal Operation Prior to Problem.pngScreenshot 2023-07-31 11.54.50 PM.pngScreenshot 2023-07-31 11.55.02 PM.png
