Battery Management And Cycle {14003 - Studer VarioString User Manual

Studer Innotec SA
VarioString

8.4.5 Battery management and cycle {14003}

The VarioString battery charger is designed to ensure a battery
charge as complete as possible. The charge process,
described in detail in chapter 7.2 is managed in 4 successive
phases of which only 3 are activated by default. Thus the
VarioString will carry out only phases 1 (bulk), 2 (absorption)
and 4 (floating) according to a charge profile as per the figure
to the right which represents the basic cycle. This basic cycle
takes place automatically.
The charge curve obtained this way depends on a whole series of parameters that may be freely
modified in order to get a charge profile that meets at best the requirements set by the manufacturer
or the user.
If the BTS-01 temperature sensor (or the BSP, battery status processor) is used, the voltage regulation
thresholds of the battery are corrected in real time according to the battery temperature. The value
of this compensation in mV/°C/cell for a reference temperature of 25°C is set by parameter {14035}
to -3mV/°C/cell.
The battery setting is carried out under the responsibility of the operator. An incorrect setting
that does not meet the battery charging methods recommended by the manufacturer
may be dangerous and/or considerably reduce the battery service life. If the factory
settings are modified, the new values must be entered in the parameter table at the end of
this manual.
8.4.5.1 Synchronisation battery cycle with Xtender {14036} (yes)
When a Studer inverter of the range Xtender is used in the system, it can transfer to the VarioTrack its
battery charge setting so that they can operate together in an optimum way. Synchronization allows
a coherent operation of multiple units which participate to the battery charging and avoids multiple
successive equalizations triggered by each charger.
When this parameter {14036} is activated, all other parameter involved in the battery cycle
are hidden and not accessible. In this case, only the maximum charging current is
adjustable.
8.4.5.2 Battery charge current {14001} (120 Adc)
See Basic Settings, chap. 8.4.4.2.
8.4.5.3 Temperature compensation {14035} (-3mV/°C/cell)
If a BTS-01 or BSP temperature sensor is used, the voltage adjustment thresholds for charging the
battery (absorption, equalization, floating...) are automatically corrected in real time according to
the battery temperature. The value of this compensation in mV/°C/cell for a reference temperature
of 25°C is set by parameter {14035} to -3mV/°C/cell. For example: for a 48V battery (24 cells of 2V) at
a temperature of 30°C, the voltage compensation is: (30-25)*24*(-3/1000) = -0.36V. For a floating
voltage value {14005} set to 54.4 V the effective floating voltage (compensated) will be 54.0 V.
8.4.5.4 Floating phase {14004}
8.4.5.4.1 Floating voltage {14005} (54.4 Vdc)
Determines the voltage applied when the battery is fully charged. This voltage prevents self-
discharge and keeps the battery to its optimum charge level.
8.4.5.4.2 Force phase of floating {14006}
This parameter may be used to force a battery cycle in progress to assume the final values of the
floating voltage phase. If the battery voltage level is higher, the charger momentarily switches out
until the new target voltage is reached.
8.4.5.5 Absorption phase {14007}
During this phase, the battery accumulates the last percentages of power to be stored. This phase
takes place at a constant voltage. Over the course of this phase, the necessary current diminishes
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