User Guide

17
USER’S GUIDE
17
5 . 2 .1. Charging Flooded Batteries
î Prior to charging, check electrolyte levels to verify that the plates are covered with electrolyte. If plates
are exposed, add enough water (distilled or deionized) to just cover the plates prior to charging.
î Make sure that vent caps are in place and are properly secured.
î Trojan recommends a 3-phase I-V-I prole for charging its ooded batteries
o Phase 1: Constant current bulk charge
A constant current equal to 10-13% of C
20
is applied as the voltage slowly increases.
The bulk phase ends when the voltage rises to the absorption voltage.
o Phase 2: Constant voltage absorption charge
A constant voltage equal to 2.35-2.45 V/cell is applied as the current slowly declines.
The absorption phase ends when the current falls to the nish current.
o Phase 3: Constant current nish charge
A constant current equal to 1-3% of C
20
is applied as the voltage increases. The nish phase
ends when the battery is fully charged. Flooded batteries will gas (bubble) toward the
end of the nish phase to ensure proper mixing of electrolyte.
o Refer to Table 5 and Figure 6 for system charging parameters and typical voltage and
current proles.
o In applications where batteries are infrequently used, it is desirable to compensate for self-discharge
by keeping a low charging voltage on the batteries. This is called the oat voltage. Avoid using
continuous oat charging on ooded batteries that are charged more than once/week.
When oat charging is used, it is started immediately after the end of the nish stage.
î Following charge completion, add water if required as directed in Section 4.2.
Table 5
Flooded/Wet Batteries - Normal Charging Parameters @ 25°C (77°F)
Trojan Battery
Line
Maximum
Charge Current*
(% of C
20
)
Absorption
Voltage**
(V/cell)
Maximum
Absorption Phase
Time (hours)
Finish Current
(% of C
20
)
Equalization
Voltage
(V/cell)
Float Voltage
(V/cell)
Temperature
Compensation
(V/cell)
Solar Premium
and
Signature
13% 2.45 4 1-3% 2.70 2.25
Fahrenheit:
-2.8 mV x
(T
battery
-77)
Celsius:
-5 mV x
(T
battery
-25)
*If charging time is limited contact Trojan Technical Support for assistance.
** In cases where the charger has a bulk voltage setting rather than a current, use the above absorption settings.