Specialty Telecomm and other weird design/use batteries do indeed have construction variances that necessitate weird recharging profiles. And I second Don's, opinion that UPS type AGM batteries need to be researched. Their quirkiness lies in the construction of negative plates.
As for flooded batteries...
The absolute OPTIMUM recharging rate is that which can fully recharge the accumulator in a 24-30 hour period of time. It'll gain perhaps 4% additional battery life. This means a 50% depleted group 27 can be successfully recharged at 3 amperes aiming for optimum lifespan despite inconvenience. However at the end of the charge cycle the low ampere recharge must revert all cell electrolyte readings to OEM new density.
Don, check your recommendations again. 27 amps seems like the minimum amperage for recharging as well. In bulk mode.
