I'm a newbie to the fancy Smart controller that Victron provides, and I wonder if my charger readings and settings make sense. I'm also not real clear as to how the specs that Crown Battery provides correspond to the settings that Victron requires in their VictronConnect app.
From having read others' experience, I believe I have the settings right, but I'd like to understand their actual meaning!
2-100W 12V solar panels in series
Victron Smartsolar 75/15 MPPT Bluetooth controller
Victron BVM-712 battery monitor plus temp sensor
2 Crown 220Ah GC2 6V standard FLA batteries in series
This is my understanding of the "bulk-absorption-float" cycle, please advise if I have it wrong...
Charging starts in Bulk mode, with max available current (up to 50A per Crown, but in reality current is limited by my panels to @ 13.2A)
The starting ''Voltage" in Bulk mode is determined by battery state of charge - and it gradually climbs to "Charged" level, which is equivalent to Absorption level (14.22V per Crown specs).
Once the SOC climbs to the "Charged" (Absorption) voltage-level, the controller switches to Absorption mode, which then limits the voltage to no more than the Absorption setting, and varies the current, gradually lowering the current, as the battery becomes more charged (as the battery accepts less and less). Question: does the controller actually keep the voltage at the 'Absorption' voltage-level (Crown calls it: 'Constant Voltage') during this Absorption phase?
When the charge current drops as low as 5A (per Crown specs) the controller should switch to Float mode (Crown: 'constant current'), and (should?) holds the current at 5A, until SOC corresponds to (controller setting of) Float Voltage (13.5V)? Question: does the controller actually stop charging at this point? ie: No 'trickle charge'?
Obviously, this last is one of my stumbling points. If Absorption Voltage is constant at 14.22V, then when the charger switches to Float mode, the battery voltage will read 14.22, won't it? In which case, 'Float' voltage will read high at this transition point? Or does the Absorption charging voltage drop as the SOC gets closer to Float?
So my confusion comes from Crown specs being unclear to me, and names of 'phases' and specifications not corresponding between VictronConnect, and Crown, and the Victron controller not having specified a 'constant current' for the Float mode
As I said, I'm new at this, and my Victron controller readings aren't following my understanding of the way it should work. For example, during the controller's Absorption mode (set at 14.22V in the app), the voltage will read 13.55V at 1.7A, which seems more like a Float to me. It's a cloudy day, but it seems it could be charging at 14.22 at 1.6A, per the Absorption app-setting. Or is this possibly the temperature compensation?
Ii appreciate any clarity anyone can give me on this!