I have a solar charging setup consisting of 2x100W flexible panels feeding a SmartSolar 75/15 and 2x Victron 115W panels feeding another SmartSolar 75/15. Both are connected to 2x Victron 165Ah AGM Gel batteries via a Lynx Shunt. There is also a Cerbo managing the system.
Using the Victron Gel 2 preset in the MPPTs sets the tail current at 1A.
It is also possibe to set the tail current in the shunt as a percentage of Ah capacity.
Question - which of these settings takes precedence?
Neither because they have 2 different functions if you read the manuals for the 2 devices.
Tail current in the mppt tells the mppt to swap from absorption to float when the charge current falls below the setting.
Tail current in the shunt tells the shunt to reset to 100% SOC when the battery current falls below the setting.
Make sure the tail current setting in the shunt is about 2 times than in the mppt so the shunt goes yo 100% before the mppt finishes charging.
As you have a Cerbo, read the Cerbo mamual on DVCC, then in the Cerbo enables DVCC, SVS and SCS then your mppts will use the shunt current and voltage which are more accurate.
Perfect - Thanks
Tail current in the shunt is set correctly & I have DVCC, SVS and SCS enabled since setup.
Sounds like I am good to go …
My question arose because the 2 MPPTs go into float at different times but 1 is a couple of years old and one is a MK2 new one.
It is hard to get the 2 mppts perfectly synchronised from a GX device, using SVS and SCS gives them the best chance, bit not always perfect.
The differences are small and even though one MPPT (the newer one) shows Absorption the system voltage is at Float.