4.3. Four stage charge curve for Lithium-Iron-Phosphate (LiFePo4) batteries
4.3.1. Bulk
Entered when the charger is started (DS-2 on and battery voltage <26V, or DS-2 off), or when the battery voltage falls below
26,7V (due to a heavy load) during at least 1 minute. Constant current is applied until absorption voltage is reached (28,4V for a
24V battery).
4.3.2. Absorption
After the absorption voltage has been reached, the charger operates in constant voltage mode.
The recommended absorption time is 2 hours.
4.3.3. Storage
After absorption charge the output voltage is reduced to storage level. This level is not sufficient to compensate for slow self-
discharge of the battery, but will maximize service life.
4.3.4. Weekly battery 'refresh'
Once a week the charger will enter Repeated Absorption-mode during one hour to 'refresh' (i. e. to fully charge) the battery.
5. MAINTENANCE
This charger does not require any specific maintenance. However an annual check of the battery connections is recommended.
Keep the charger dry, clean and free of dust.
6. TEMPERATURE COMPENSATION
Figure 7
Absorption
Float
10 °C
25 °C
50 °C
Battery temperature
Figure 9
12