8
The recondition stage may also be applied to flooded batteries occasionally to equalise individual
cell voltages and prevent acid stratification.
During recondition stage the charge current is limited to 8% of the nominal charge current, (for
example - 1.2A for a 15A charger) and the stage is terminated as soon as the battery voltage
increases to the configured recondition voltage or after a maximum duration of 1 hour (or as
configured).
5. Float
The battery voltage is maintained at the configured float voltage to prevent discharge.
Once float stage is commenced the battery is fully charged and ready for use.
The float stage duration is also adaptive and varied between 4 to 8 hours depending on the
duration of the absorption charge stage, at which point the charger determines the battery to be
in storage stage.
6. Storage
The battery voltage is maintained at the configured storage voltage, which is slightly reduced
compared to the float voltage to minimise gassing and extend battery life whilst the battery is
unused and on continuous charge.
7. Refresh
To refresh the battery and prevent slow self-discharge while in storage stage over an extended
period, a 1 hour absorption charge will automatically occur every 7 days (or as configured).
3.2 Temperature compensation
The Victron
Blue Smart Charger
range will automatically compensate the configured charge voltage
based on ambient temperature (unless disabled or in Li-ion mode).
The optimal charge voltage of a lead acid battery varies inversely with battery temperature;
automatic temperature-based charge voltage compensation avoids the need for special charge
voltage settings in hot or cold environments.
During power up the charger will measure its internal temperature and use that temperature as the
reference for temperature compensation, however the initial temperature measurement is limited to
25°C as it’s unknown if the charger is still warm from earlier operation.
Since the charger generates some heat during operation, the internal temperature measurement is
only used dynamically if the internal temperature measurement is considered reliable; when the
charge current has decreased to a low/negligible level and adequate time has elapsed for the
charger’s temperature to stabilise.
The configured charge voltage is related to a nominal temperature of 25°C and linear temperature
compensation occurs between the limits of 6°C and 50°C based on the default temperature
compensation coefficient of 16.2mV/°C (for 24V chargers multiply the coefficient by 2) or as
configured.
