Dometic BUTTNER MT BCB25/20, Installation And Operating Manual

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20 4445103694
Connection variant C (fig.
e
, page 9)
Connection variant for motor homes with existing
central electrical system.
• The load relay is controlled via the TR terminal.
After the engine started, the relay remains
closed and allows charging currents of more
than 25 A. When falling below this current the
battery control booster opens the load relay and
takes over the charging process.
• For LiFePO4 batteries: The load relay is activated
via the TR terminal in accordance with the tem-
perature to ensure the controlled charging of
the house battery at extreme temperatures
(<0 °C and >50 °C).
The integrated cutoff relay remains opened if
the temperature reaches <0 °C or >50 °C.
• When connected to the mains only the house
battery is charged. Simultaneous trickle
charging of the starting battery with a maximum
of 1 A is only available if the central electric sys-
tem provides an auxiliary charging output for the
starting battery.
I
1. Slide the DIP switch (fig.
2
1 , page 3) to the
“V” position.
2. Disconnect the existing cable between the
house battery and the central electrical system
at a suitable point. Connect the two cable
ends to the distribution block.
3. Choose a suitable location for the load relay
holder considering the cable length of the wir-
ing harness.
4. Insert the load relay into the load relay holder.
5. To connect the battery control booster, the
load relay and the distribution block proceed
as shown in fig.
e
, page 9.
No in
fig.
d
,
page 8
Description
1 Ground (chassis) or negative terminal of the
house battery
2 Temperature sensor probe
3 Cutoff relay (normally open relay/NO)
NOTE
• In mains operation, the charging cur-
rents of the integrated charger and the
battery control booster are added up.
• For LiFePO4 batteries: Disable the
integrated charger if it is not equipped
with temperature-controlled charging
and the charging characteristic for
LiFePO4 batteries.
• For LiFePO4 batteries: Temperature-
controlled charging only works if the
originally integrated charger also
features temperature compensation.
No in
fig.
e
,
page 9
Description
1 Ground (chassis) or negative terminal of the
house battery
2 Temperature sensor probe
3 Integrated cutoff relay of the central electri-
cal system
4 Existing cable between the house battery
and the central electrical system
5 Distribution block
6 Load relay (normally closed, 12 V/100 A)