Forum Discussion
brulaz
Apr 15, 2017Explorer
His recommendations seem designed for those with a low ratio of solar W to battery Ah.
For my system, (700W solar, 440Ah batts) I would be concerned about setting the float V as high as absorb V.
We do raise our solar charger's float V when actively boondocking, but when not using much current I drop it down to 13.2V. Otherwise I'd just be boiling off water without increasing the charge.
Otherwise, yes, the batteries get hammered at least once a day with the absorb setpoint of 14.9V, temperature compensated, and absorb doesn't stop until the current drops to about 0.6% of Ah capacity. That's full as far as I can tell. And when in storage with full sun, it takes less than 5 min. The rest of the day is float.
After a stretch of solar undercharging, I equalize at 16V for 1-2hrs.
Have heard concerns elsewhere that these higher absorb voltages like 14.8-14.9V might be hard on trailer electronics. Especially as temperature compensation can raise them well into the 15's. But so far, all is working as it should ...
For my system, (700W solar, 440Ah batts) I would be concerned about setting the float V as high as absorb V.
We do raise our solar charger's float V when actively boondocking, but when not using much current I drop it down to 13.2V. Otherwise I'd just be boiling off water without increasing the charge.
Otherwise, yes, the batteries get hammered at least once a day with the absorb setpoint of 14.9V, temperature compensated, and absorb doesn't stop until the current drops to about 0.6% of Ah capacity. That's full as far as I can tell. And when in storage with full sun, it takes less than 5 min. The rest of the day is float.
After a stretch of solar undercharging, I equalize at 16V for 1-2hrs.
Have heard concerns elsewhere that these higher absorb voltages like 14.8-14.9V might be hard on trailer electronics. Especially as temperature compensation can raise them well into the 15's. But so far, all is working as it should ...
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