Manual

975-0526-01-02 29
Installing Batteries
Three-Stage Charging
The three-stage charging mode employs the following sequence: Bulk,
Absorption, and Float. During the Bulk stage the batteries are accepting a
constant maximum current. In the Absorption stage, the battery voltage is
held constant and the current declines. A battery will “gas” (produce
hydrogen and oxygen) when its voltage exceeds the “gassing” voltage.
Finally, in the Float stage, the charger continues to provide voltage at a
lower level to maintain the battery in a fully charged state. If there is no
load on the battery, it will typically draw very little current. The charger,
however, is able to provide current to its full rating to power auxiliary DC
loads on the battery.
The charger will restart the charging cycle in the Bulk stage if the lowest
battery voltage of the three banks drops below 12.5 V (12 Vdc chargers) or
25 V (24 Vdc chargers) for 15 minutes. After seven days, the charger will
automatically restart charging in order to refresh the batteries.
Figure 9 Three-Stage Charging Process
Battery Voltage
Time
ABS
CC
ABS
CV
ABS CV timeout
max 5 hrs
FLOAT timeout
max 7 days
Total ABS timeout
Start of
charging cycle
max 8 hrs
FLOATBULK
Vgas voltage
Vbat = Vgas
for 1 minute
Vbat < 12.5 V
for 15 minutes
Vbat = Vabs
for 1 minute for 1 minute
lout < 10% lrating
Charge
start
TC2 204060 Series BattChg Owners Guide.book Page 29 Friday, July 8, 2011 11:44 AM