More Solar for "Us"
Ok, I went off.the deep end? Bought 3 used 37watt uni-solar panels and a blue sky 2000e controller for the hefty price of $400, They were being listed as 75w panels, they are not The tested open...
Forum Discussion
The Blue Sky solar controller has the "true multi-stage" smart charger profile. How can it "force" the battery to take higher amps? Amps taper as required to prevent overheating etc. Amps still taper wrt to the battery's "natural acceptance rate" (defined as the max amps without overheating at an SOC--so max amps keeps dropping as SOC rises) as SOC rises whether that rate is for 14.7v or 14.0v.
How can the controller crank out so much more than the battery will accept and create this gassing problem when it is designed to not do that?
Also just what amps are we talking about for the SOC involved? It seems that in the 14v range the acceptance rate at 80% is about 15amps per battery and at 90% it is down to about 5 amps per battery.
After that it continues to taper. Some define "fully charged" as both 97% SOC and when acceptance rate has fallen to 2% of ah capacity. That would be 2 amps on a 100ah battery.
This suggests that on a pair of batteries, at 10 amps from solar, the controller will deliver constant 10amps till the bank is at about 90% SOC when amps will then taper properly to about 4 amps at 97% SOC.
Where is this overcharging /gassing threat?
At that 97% SOC point some chargers will just stop or else shift down to their Float voltages.
How can the controller crank out so much more than the battery will accept and create this gassing problem when it is designed to not do that?
Also just what amps are we talking about for the SOC involved? It seems that in the 14v range the acceptance rate at 80% is about 15amps per battery and at 90% it is down to about 5 amps per battery.
After that it continues to taper. Some define "fully charged" as both 97% SOC and when acceptance rate has fallen to 2% of ah capacity. That would be 2 amps on a 100ah battery.
This suggests that on a pair of batteries, at 10 amps from solar, the controller will deliver constant 10amps till the bank is at about 90% SOC when amps will then taper properly to about 4 amps at 97% SOC.
Where is this overcharging /gassing threat?
At that 97% SOC point some chargers will just stop or else shift down to their Float voltages.
