After a year of use our system has recently started raising high voltage alarms and I am wondering if I have a problem as I am not aware of anything having changed in the setup.
The setup is:
* Bank of 2 Victron AGM 100A connected to a Victron 100/30 MPPT and monitored by a BMV 702 which also monitors battery tempreature
* Bank of 2 Upower AGM 110A connectyed to a Victron 100/50 MPPT not currently monitored as I am replacing the NASA marine BM1 monitor with a BMV 702 and have not completed the installation because of difficulty of access.
* Shore power charging via a Sterling procharge 40A which is connected to each battery separately (supports up to 3 banks).
* Victron Cyrix-ct VSR is used to share charge between the battery banks when shore power is not switched on and a circuit breaker is used to isolate the battery banks when shore power is on.
The system is in our boat which is currently hooked up to shore power. The problem started a few weeks ago: when shore power was disconnected and then reconnected the voltage whould spike and take a while to come down. We switched of the mains charger as we could manage on solar but we are still getting an alarm when the sun is sufficiently strong to initiate charging, thougth the alarm is at a lower voltage and clears more quickly.
I am not getting any low voltage alarms on the battery so I don't think they are getting discharged to a low level, and when we were getting alarms with the mains charger connected the batteries were pretty much full.
The mains charger and MPPTs are set at the default settings for AGM batteries.
The BMV has the high voltage alarm threshold set at 14.7 and clearing at 14.5. I am contemplating setting the threshold to the fast charge voltage of 14.9.
The only thing that I can think of as being different is that the water temperature may be lower (about 11 degrees C) than when we commissioned the system.
