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Note: If a temperature sensor is not used, you must manually adjust charging voltages based on the battery temperature when in use.
If the charger has a preset charge profile for GEL type batteries, verify that these settings follow recommended charge settings.
4.1.1 Charge Parameters
The charge voltage should be set as shown in the table below.
Nominal System DC Voltage
12V
24V
48V
Maximum Charge Current
0.2 C10
Maximum Absorption Time
4 hours
Bulk & Absorption Charge Voltage
14.2V
28.4V
56.8V
Float Voltage
13.8V
27.6V
55.2V
Balancing Voltage
14.8V
29.6V
59.2V
Voltage Regulated Charge profile (IUU charger) at 25°C / 77°F
4.1.2 Balancing charge
To avoid permanent capacity loss and sulphation in cycling operation the goal is to achieve a complete recharge (100% SoC)
after every discharge. Capacity loss and sulphation will threaten the battery’s state of health.
The less complete the daily recharge is, the more frequently a balance charge will be required to protect the battery from
sulphation and lagging batteries. Depending on the cycling frequency, a balancing charge is recommended every 60 to 180
days. When short charging times are used then balancing charges are required at frequent intervals, preferably every month.
Balancing charges are also required after incidents of excessive stress for the battery (deep discharges with inadequate charges)
or when the individual battery voltages show excessive deviation from the average (lagging batteries and sulphation problems).
Should the voltage in individual batteries deviate from the average value more than the following limits, perform a balance charge.
Balance charge is generally required when the total spread between batteries is greater than 0.04V.
4.1.3 Commissioning Charge
Batteries lose charge while in transit or during storage. For this reason, a refresh charge should be given before putting
the battery into service. The battery should be considered fully charge when individual battery voltages have not risen for a
period of 4 hours. The surface temperature must not exceed 55°C (131°F). Recommended charge settings are as follows:
Nominal System DC Voltage
12V
24V
48V
Bulk & Absorption Charge Voltage
14.2V
28.4V
56.8V
Current Limit
10A per 100Ah C10 rating
Time Limitation
Max. 6hrs
Commissioning / Refresh charge settings (25°C/77°F)
SELF-DISCHARGE CHARACTERISTICS
Loss of
Capacity
(%)
Storage Time (months)
0
1
2
6
8
10
0
20
40
60
80
SOPzV Blocks
5
4
3
7
9
10
30
50
70
25˚C
35˚C
45˚C
