User Manual

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Constant Current Charging
This charging method is not often utilised for valve
regulated lead acid batteries, but is an effective method
for charging a number of series connected batteries at
the same time, and/or as an equalising charge to correct
variances in capacity between batteries in a series group.
Extreme care is required when charging NP batteries
with a constant current. If, after the battery has reached a
fully charged state, the charge is continued at the same
rate, for an extended period of time, severe overcharge
may occur, resulting in damage to the battery. Figure 16
shows a typical constant current charging circuit; Figure
17 shows the characteristics of two NP6-12 batteries under
continuous overcharge conditions.