jj5406 wrote:
...following information in the owner"s manual:
When pushing the “BATT” switch, the highest LED light illuminated indicates the estimated auxiliary battery condition. C = charge at 12.7 volts, G = good at 12.1 volts, F = fair at 11.6 volts, L = low at 6.0 volts....
Whoever wrote that part of the manual is absolutely incorrect and their keyboard should be confiscated. The other part of the manual has much more accurate info.
A deep cycle battery can be regularly discharged to 50% with no ill effects. It can be safely discharged to 30% but drastically shortens the battery life. In comparison a starting battery should never be discharged lower than 80%.
Many of us have two batteries, four batteries, or even more wired together to increase the available amperage.