Operation
057-231 ISSUE: 2
Page 26 of 30
5.4.3
FLOAT CHARGE
The battery charger DC voltage is lowered to the configured f
loat voltage
.
Float Charge is used to provide a small amount of current to the battery, to overcome internal losses
and keep the battery at it’s 100% charged state. The battery can be left in this mode indefinitely.
5.4.4
STORAGE
When configured to use a four stage charging profile, a time limited storage charge is periodically
entered (
storage timer
) to maintain the battery charge at optimum levels. This occurs at the level of
the
storage voltage
. This is adjustable using the DSE Configuration Suite PC Software.
When the
storage timer
expires, the charger re-enters the
Absorption
mode.
Additionally, this is used as an ‘Automatic Boost’ facility, to periodically attempt to remove sulfation
from the battery plates.
5.4.5
CHARGING TIME
Charge time is often of little consequence when the battery is used in a
standby
operation. An
example of this is when the battery is used to supply the starting system of a diesel generator. During
normal operation, the battery is at full capacity and the battery charger is used to maintain the float
voltage of the battery. The battery is only drained when the generator is called to start. As the
generator has a DC charging alternator fitted, the battery is quickly recharged when the generator is
running. Should the generator stop before the battery is fully recharged, the DSE9474 & DSE9484
Battery Chargers will continue to recharge the battery until it is fully charged.
Typically a battery will charge from flat to 80% capacity in 16 hrs when charged at C/10.
For example charging a 50 Ah battery for 16 hrs at 5 A will charge the battery to 80% of its full
capacity.
Remember to take into account any other standing load such as control panel requirements when
calculating how much power is ‘left’ to charge the battery.
5.4.6
MANUAL BOOST
NOTE: The Digital Input must be configured to
Manual
Boost to provide this function.
For further details, refer to DSE Publication:
057-159 DSE94xx Configuration Suite PC
Software Manual.
Manual boost will place the charger into
Bulk
Charge mode, charging at the level of the
boost voltage
.
A typical use of manual boost is with Lead Acid type batteries. When the battery is fully charged,
placing the charger into boost mode will raise the output voltage. This has the effect of
gassing
the
battery, helping to remove sulfation from the battery plates and helping the cells to
equalise
in
voltage.
5.4.7
TEMPERATURE COMPENSATION
NOTE: For further details of PC Configuration, refer to DSE Publication:
057-159
DSE94xx Configuration Suite PC Software Manual.
If temperature compensation is enabled through configuration, and remote temperature sensor is
connected, the output voltage automatically varies by a configurable voltage per cell for each 1 °C
deviation from 20 °C, within the range of -20 °C to 60 °C. Increasing temperature gives decreasing
output voltage and increasing temperatures gives increasing output voltage.
The battery temperature is measured by a 2 wire PT1000 sensor placed on the battery itself.
