Installation Manual

89-041 Section 4 Issue 5 S4-7
Power supply
Connected to the ship’s 24V DC emergency power source through a 2-pole switched fused
supply to allow isolation for servicing. The power requirements are 24V DC +30% -10%, 3.5A
maximum.
Standby power requirement 21 W; 0.9 Amp at 24V DC
Peak power requirement 75 W; 3.5 Amp at 24V DC
Required conductor area as a function of cable length
Power cable length Required conductor area
0 – 10 metres 0.75 mm
2
10 – 20 metres 1.5 mm
2
20 – 40 metres 3.0 mm
2
Isolation between the power supply connections and any other connection to the transponder is
1kV minimum.
The DC power source should comply with IMO guidelines for the class of vessel concerned.
National authorities and classification societies may have their own power supply requirements
that should also be considered.
If the available supply is AC, a converter, P/N 89-029, is available as an option.
DISP port - Display VDU
The DISP port connects the VDU Display unit with the Transponder. This port is vital to the
functionality of the transponder and the VDU and must be connected. To prevent any
malfunction of this port it is not possible to change the configuration.
Display cable:
Four twisted pairs, screened, PVC sheathed.
Cable length to display Required conductor area
0 – 100 metres 0.8 mm
2
each wire
100 metres + 1.5 mm
2
each wire
The connection between the Screw terminal board and the VDU unit is given below, showing
the rear of the VDU and the 15-pin connector, and the pin identification of the connector.
Transponder VDU pin
Rx common 2
Rx B 1
Rx A 6
Tx A 12
Tx B 13
Tx common 8
+ Bat out 3
- Bat out 4
The twisted pairs are assigned as (Rx A/B), (Tx A/B),
(common pair) and (battery pair)
The DISPLAY port can be connected to a Personal Computer, but two precautions are
necessary: special software is required to display the received information, and usually it is
necessary to convert the RS 422 signal from the transponder to a RS-232 signal in order to
interface to the PC.