2.7.3 - Float Mode
Figure 3. Charge profile for Float Mode
Figure 3 defines the charge profile for the Float Mode. In this mode of operation,
batteries are maintained at full charge. In addition to maintaining full charge, the
charger can support a load current – as long as the combined load current and
battery charging requirements do not exceed the output current defined in the
Constant Current setpoint (Icc, default value of 20A in the Basic Mode).
In this mode of operation, the charger will go through bulk charge and Constant
Voltage modes as previously described. It then goes into standby until the battery
voltage drops 0.4V below the Float Voltage (Vfloat, default value of 26.8VDC in
Basic Mode) setpoint. The charger will then reactivate and maintain float voltage
as long as the current requirement is above 2A. If current drops to 2A, the charger
will again enter standby mode. The charger will continue this cycle of
standby/reactivation until power is removed or until the Model 1311 programmer
is connected.
Curtis 1620 Manual
page 5
2.7.4- Equalize Mode after Float Mode
Figure 4. Charge profile for Equalize Mode after Float Mode
Only flooded lead-acid (FLA) batteries require equalization. In order to prevent dam-
age to the battery, the charger will go through the equalization process once, automati-
cally returning to the charge profile being utilized immediately before the equaliza-
tion. The Model 1620 provides the option of equalizing batteries, without need for
separate power sources, in order to extend battery life.
Figure 4 defines the charge profile for the Equalize Mode if the previous charge
profile was Float Mode. This profile behaves similarly to the Equalize Mode
(after Off Mode) except that after the equalization stage the charger will immedi-
ately enter standby. It will then behave as described in the Float mode – reactivat-
ing after the battery voltage drops 0.4V below Vfloat.
Curtis 1620 Manual
page 6
