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INSTRUCTIONS FOR DANFOSS BD35/BD50F
12-24 V DC
The electronic unit is a dual voltage device. This
means that the same unit can be used in both 12V
and 24V power supply systems. Maximum voltage is
17V for a 12V system and 31.5V for a 24V power
supply system. Max. ambient temperature is 55°C.
The electronic unit has a builtin thermal protection
which is actuated and stops compressor operation if
the electronic unit temperature gets too high.
Installation (Fig. 10)
Connect the terminal plug from the electronic unit to
the compressor terminal. Mount the electronic unit
on the compressor by snapping the cover over the
screw head (1).
Power supply (Fig. 10)
The electronic unit must always be connected
directly to the battery poles (2). Connect the plus to
+ and the minus to -, otherwise the electronic unit
will not work. The electronic unit is protected
against reverse battery connection. For protection of
the installation, a fuse (3) must be mounted in the +
cable as close to the battery as possible. 15A fuse for
12V and 7.5A fuse for 24V circuits are
recommended. If a main switch (4) is used, it should
be rated to a current of min. 20A. The wire
dimensions in Fig. 11 must be observed. Avoid extra
junctions in the power supply system to prevent
voltage drop from affecting the battery protection
setting.
Battery protection (Fig. 10)
The compressor is stopped and re-started again
according to the decided voltage limits measured on
the + and - terminals of the electronic unit. The
standard settings for 12V and 24V power supply
systems appear from Fig. 12. Other settings (Fig. 13)
are optional if a connection which includes a resistor
(9) is established between terminals C and P. In
solar applications without a battery a 220 kW
resistor is recommended. In AEO (Adaptive Energy
Optimizing) speed mode the BD compressor will
always adapt its speed to the actual cooling demand
within a random operation voltage of 9.6 to 31.5V.
Thermostat (Fig. 10)
The thermostat (7) is connected between the
terminals C and T. Without any resistor in the
control circuit, the compressor with electronic unit
101N0210 or 101N0220 will run with a fixed speed
of 2,000 rpm when the thermostat is switched on.
With the thermostat directly connected to terminal C
the electronic unit 101N0300 will adjust its speed to
the actual cooling demand. Other fixed compressor
speeds in the range between 2,000 and 3,500 rpm
can be obtained when a resistor (8) is installed to
adjust the current (mA) of the control circuit.
Resistor values for various motor speeds appear
from Fig. 14.
Fan (optional, Fig. 10)
A fan (5) can be connected between the ter
and F. Connect the plus to + and the minus to F.
Since the output voltage between the ter and
F is always regulated to 12V, a 12V fan must be
used for both 12V and 24V power supply systems.
The fan output can supply a continous current of
0.5Aavg. A higher current draw is allowed for 2
seconds during start.
LED (optional, Fig. 10)
A 10mA light emitting diode (LED) (6) can be
connected between the terminals + and D. In case
the electronic unit records an operational error, the
diode will flash a number of times. The number of
flashes depends on what kind of operational error
was recorded. Each flash will last ¼ second. After
the actual number of flashes there will be a delay
with no flashes, so that the sequence for each error
recording is repeated every 4 seconds.
