Quote:
Originally Posted by sgt_doofey
That's what's confusing me!
I've got a 75Ah AGM battery in a battery box with a 150W solar panel and 10A solar controller to charge it up.
My understanding of AGM batteries is that you shouldn't discharge them below 50%. This is a voltage of about 12V if I'm not mistaken, whereas fully charged it's somewhere around 13V.
If I were to select option 3, that would discharge the battery down to around 9.6V, which could end up damaging the battery as it would be close to fully discharged. 
Option 1 of 11.1V and option 2 of 11.5V are also both under the 50% limit for AGM batteries. |
It kind of depends how often you discharge to those levels as to how badly the battery life will be affected. If it's only a handful of times a year, and the battery is stored properly in between times, then it probably won't matter.