My houseboat is fitted with a 48V LiFePO4 (15S 2P) battery with a capacity of 17 kWh. I have installed on it four solar panels of the type Trina Solar with a nominal power of 400W each.
I have grouped the panels in two series of two, which gives for each series a voltage of about 76V. Each series is connected to a Victron MPPT 100/20 48V regulator. The outputs of both regulators are connected to the battery. On the panel input and on the battery output of each regulator, I have inserted circuit breakers, thus a total of 4 breakers.
My boat is exclusively meant for sailing on the inland waterways. So the solar radiation is very often intercepted by trees, bridges, buildings, etc. What is specific to this application is that, unlike solar panels installed on house roofs, the interruptions due to obstacles while sailing can have a short duration: sometimes a few seconds only.
The effect I want to report here is that it happened several times that after passing under a bridge, one of the regulators would not restart transferring the power from the solar field to the battery. I often monitor their state using the Victron Connect app on my smartphone, and when this happens, I find :
Solar field voltage: 76V
Solar field current: 0.0
Power: 2W.
Sometimes, the correct operation is restored after several minutes, sometimes not. To recover the normal operation, I switch the solar field circuit breaker off, then I wait for 2 or 3 seconds, then I switch it on again. The normal operation resumes immediately.
The smartphone application has been automatically updated a few weeks ago, and if I understand correctly, the regulator firmware was also updated at the same time. The behavior I describe existed before the update, and has not changed after the update.
Both regulators are identical and exhibit the same behaviour, but their failing to find the MPP is totally independant of the other regulator. I never saw both regulators failing at the same time.
