donn0128 wrote:
CA 675
RC 180
CA 845
This is the ratings of a single GP27 battery. So take it as you will. Two T105s like everyone try to tout as the best will have what once you have them hooked to give you the required 12VDC?
Forget so called RC - Reserve Capacity - it's a deep cycle battery's 20 HR rating that is the most useful reference. A 6 volt GC-2 deep cycle battery like the Trojan T-105 will have a 20 HR rating of about 220 AH but because 6 volts are wired in series to create 12 volts the AH rating remains the same - about 220 AH. A 12 volt G31 is typically 20 HR rated around 105 AH to 110 AH so two in parallel will be rated around 210 AH to 220 AH, the same territory as a pair of GC-2s. Smaller G27 12 volt jugs are typically 20 HR rated around 85 AH so two of those in parallel would be 20 HR rated around 170 AH. As for cost a pair of GC-2 flooded batts are most often the best deal around because so many of them are manufactured and sold every year. I should know - this spring I replaced my aging G27 flooded with a new G31 AGM and it was anything but inexpensive. :E
