Service manual CS3000
Chapter 3: Output board UTK-2 3-25
The circuit boards of the central unit
Document no.:
S-4-007.875/E
Prepared:
1995-03-17 Fia
Revision:
R4 2004-03-15 BM
© 2002, Consilium Marine AB
1. DC/DC converter
The DC/DC circuit converts the battery voltage of the back plane to 5 VDC,
which is supplied to all logical circuits on the board. Should the voltage
disappear, a signal is activated in the back-plane.
2. Supervision
The battery voltage is fused. If the fuse is blown a signal is activated in the
back-plane. The fuse is accessible on the front panel of the board, and can be
used for disconnecting the power.
3. LED indications
On the front panel are two green LEDs for indicating 5V power and normal
polling.
4. Control logic
The control logic is used for decoding the address bus and for generating
selection signals for read buffers and output buffers.
5. & 6. Buffers
The address bus, the data bus and the control signals are buffered before
entering the board.
7. Output status
The value written to the outputs can be read, to check the function of the
board.
8. Output latch
The output latches also functions as drive circuits for the opto switches.
9. Opto-isolated outputs
The outputs are divided into six groups, where each group has a common
positive conductor. The load is connected between the output and ground.
Each output is protected by a varistor and a freewheel diode for inductive
loads.
Technical data
Board size:
Single Europe board, 100x160 mm
Front panel:
Anodised aluminium, width 6 TE (30.1 mm)
Ambient temperature:
-10
°
C - +70
°
C
Ambient humidity:
96% Rh
Input power:
U
in
: 24 VDC (-20% - + 25%)
Current consumption:
I
in nom
: 15 mA
I
in max
: 55 mA
Outputs
24 opto isolated, transient protected in six groups with common positive
conductor
Output
voltage:
U
out max
: 35 VDC
Output
current:
I
out max
: 50 mA
Voltage
drop:
U
max
: 1.2 VDC @ 50 mA
Leakage
current:
I
out max
: 3 mA @ 70 C
