I have 2 similar systems coupling a Victron 100/30 connected to 2 PV modules in parallel with a 24V AGM battery storage of 115Ah. The main difference between systems are their location either cold or hot climate.
Parallel PV connection was preferred to series to avoid reaching Voc above 100V in cold area. Voc=45.3V@STC; beta=0.27%/oC; Vmpp=37.4V@STC; Vmpp=35.5V@NMOT(43oC); Ppv=405W@STC
The battery setpoints are user-defined as 29.4V for absorption and 27.2V for float.
The charge controller has no issues maintaining the setpoints in cold climate (0-10oC ambient). For the system in hotter climate (25oC ambient), the batteries still seem to charge going through bulk, absorption and float. However, the setpoints are lower than set with around 28.6V for absorption and 26.5V for float. I verified that the Victron still have the proper setpoints. The battery voltage levels were also validated by a second set of measurements (other than the Victron data). VPV is measured by Victron at 40-44V in cold climate and around 35V in hot climate.
Are these battery setpoints too high for the 100/30 charge controller with parallel PV connection? or would that come from the battery behaving differently in hotter environment? or else?
If the problem come from low PV voltage, what impact would that have on the batteries?
Thanks by advance for any clues and recommendations