Monkey, your battery is taking a "float" charge - that's a "fake" charge.
Batteries do that.
They hold onto the most recent charge and your meter will show a higher charge than the battery can deliver for more than a few minutes.
"Fake" - "Float" same deal.
12.06 volts is 25-percent battery charged.
See the picture:
http://www.eaglecapowners.com/campergallery/gallery/Modifications/battery-state-of-charge.pdfReddog1, A "fully" charged battery is when all the lead fins in a lead-acid battery are holding all the electrons that they possibly can. A "full" charge takes longer than you might think.
According to the techies at Power Dynamics, a 25-percent charged battery will take approximately 35-hours to reach "full" charge!
(Based on using a Power Dynamics 9100 converter at normal charge.)
Here's is a saved reference from the Power Dynamics Charge Wizard instruction booklet:
http://www.eaglecapowners.com/campergallery/gallery/Documents/Charge_Wizard_graph.pdf