Rob asks:

<<
how much amperage does
one need to apply to keep a 27 ampere hour battery topped off. Or better yet
what amperage and voltage ie watts is needed to top off a battery on a
continuous cycle?>>

Rob:

The trickle charge power applied to a battery must be greater than the self discharge rate of that battery. The self discharge rate varies considerably with temperature. At 77 degrees F the battery will discharge to 50% capacity in 12 months, 8 months at 90 degrees F. So, if  27 Ah/ 2 =13.5 Ah and there are 5760 hours in 8 months then 13.5/5760 = 2.3 milliamps (not much). You need to add to this any parasitic loads in the system like clocks or other components that draw a small current even when off. The recommended trickle charge voltage is 13.6 to 13.8 volts and regulating the voltage is important to battery life. Too much voltage and the battery will tend to electrolyze it's water. Your 200 mA charger has plenty of power but it is the voltage that is critical. These types of chargers are poorly regulated so checking the voltage without a load will not give accurate results.

Your, or any, trickle charger you use should be checked after a day or two of charging by measuring the terminal voltage at the battery with an accurate volt meter. Be sure it does not exceed 13.80 volts DC.

More information on these types of batteries is available at:

http://www.panasonic.com/industrial/battery/oem/chem/seal/index.html

According to B&C, they do not sell the Panasonic batteries but the information provided at the Panasonic site is pretty much generic to this type of battery.

Regards
Brent Regan