6.4
Battery Recharging
The illustration below shows the battery recharge process after a full discharge.
The recharge process typically consists of three periods. During the first period, the charging
current is maintained at approximately 20.0 amperes. This current is the maximum value that
can be used to charge the batteries (for minimal recharge time) while assuring safety and
long battery life.
In the second period, constant-voltage control starts and the current gradually decreases as
the batteries charge to the fully charged state.
In the third period, a trickle current continues to flow into the batteries to maintain the fully
charged status at the normal DC Voltage level.
A full recharge requires approximately 24 hours (90% recharge in 10 hours) after a complete
discharge.
The following table shows the rated maximum and minimum battery voltages, and the
charge current for each of the sizes for 75°C operation.
T O S H I B A
Rated Battery Voltages
V float
V min
I charge
39
332 VDC
214 VDC
20.0 Amps