I installed a 100/30 solar controller
And it goes into float way too early
Today it charged my battery to 77% and went into float.
What changes can i make to get it to stay in bulk until battery is closet yo 100% its wasting alot of solar.
This is what i am using
3-200 watt renogy solar panels in series
100/30 solar controller (i am upgrading this one soon)
smart shunt 1000
Epoch essentials 460 battery
Has the battery got to the absorp voltage of 14.2v?
Post the detailed mppt history.
Also the SmartShunt “Charged voltage” should be .1-.2v below the absorp voltage.
Absorb voltage on mppt is set at 14.2
Charged voltage on shunt is set at 14.2
So i should set the charged voltage on the shunt to 14.00 or 14.1
@aztec1382 the absorption duration on the controller is set to “Fixed” at 2.5 hours. If that period is fixed, at the end of 2.5 hours it will go into float even if the battery is not charged.
Try 14.0v.
The tail current is usually 2-4%.
Once the battery gets to 14v, and the tail current drops below the set point, for the charge detection time. the Soc will sync (reset to 100%).
Thank you for the responses
What should the absorption time be set at
Thanks
Kinda depends, 3 answers.
First answer is as per batt manufacturers data.
Second answer depends on how often the battery gets a full charge
One full charge a week, less absorp time.
One full charge a month, more absorp time.
Third answer, higher charge currents need longer absorp times.
Lower charge currents need shorter absorp times.
The required time in absorp is due to the need to balance the battery cells.
Hello @aztec1382 …. You could try making the charge profile “adaptive” and test it…. You could also set the absorption time to 8 hours and see if it resolves your problem. If that resolves it consider a shorter absorption time then.
Thank you for everyones replies
I
@aztec1382 that is great but please set the “Charged Voltage” slightly below the Absorption voltage as mention by @water_rat earlier in this thread. This is important because when the charged voltage is reached and the charging current is reduced to the tail current, the battery is deemed to be full by the smartshunt and is synchronised then to 100%.
This is important as small variations in the physical characteristics of the battery versus the settings of efficiency and peukert value cause the SOC over successive charge/discharge cycles to drift from reality. This synchronisation process resets the SOC to a known point where the battery is at 100% SOC.
If you make it exactly the same as absorption voltage, small variations in reading accuracy may result in the “charged voltage” never being seen by the smartshunt and therefore never actually syncing. Best to make it 0.1 or0.2 v below the absorption voltage to ensure the syncing process works.
