BÜTTNER ELEKTRONIK – Batterie-Control-Booster MT BCB 30/30, MT BCB 40/40, MT BCB 60/40
EN
27
4.8. Function of temperature sensor
The temperature sensor measures the
battery temperature and depending on
the set battery type, either influences the
charging voltage for lead batteries or the
charging current for LiFePO
4
batteries.
4.8.1. Lead acid-, Gel-, AGM-batteries:
At low temperatures, the charging voltage
is increased to compensate for the inertia
of the battery and to achieve full state of
charge. However, to protect connected
voltage-sensitive consumers, the voltage
is also limited at extreme cold conditions.
At summer temperatures, the charging
voltage is reduced, thereby reducing the risk
of gassing and loss of liquid, in particular
of gas-tight batteries (SLA, VRLA, etc.) and
significantly increasing the service life.
Battery protection: If the battery tempe-
rature is too high (more than +50°C), the
charging voltage is strongly decreased to
safety charging voltage of approximately
12.80 V and the maximum charging cur-
rent reduced to 50 % for protection
(LED “Batt. I” flashes). Battery charging
will then no longer take place, but any
connected consumers will continue to be
supplied by the charger until the battery is
within the permissible temperature range
and charging automatically can be continued.
A missing sensor is recognized by the BCB
and the charging voltages recommended
by the battery manufacturers then will be
set for conditions at 20°C.
IU
1
oU
2
oU
3
-presentation of the tempera-
ture-compensated charging programs for
lead acid batteries
Charge program “Lead Acid/AGM 1”
Charge program “Gel”
Charge program “AGM 2”
Char
ging v
olt
age (V)
Battery temperature (°C)
U1 with TS
U2 withTS
U1 without TS
U2 without TS
U3
Char
ging v
olt
age (V)
Battery temperature (°C)
Char
ging v
olt
age (V)
Battery temperature (°C)
U1without TS
U1 with TS
U2 without TS
U3
U2 withTS
U1 without TS
U2 without TS
U3
U1 with TS
U2 with TS