The total length of screened core cable
connected to the serial bus (connectors Al
should not exceed 30m
Similarly, the total
length of interconnecting cable to the
should not exceed 20m (60’). If it is necessary to
exceed the above maximum length
recommendations, please consult Nautech’s
Engineering Department for specific advice. In
general the length of interconnecting cables
should be kept to an absolute minimum to reduce
the possibility of interference by other electronic
equipment.
All cables should be run at least 1 m (3’) from
existing cables carrying radio frequency or pulsed
signals, and should be clamped at
(1.5’)
intervals.
2.3.2 DC POWER SUPPLIES
Refer to (Fig. 31)
Flexible connection tails fitted with insulated
spade connectors are supplied with the course
computer to connect the main power supply (Blue
and Brown) and drive unit motor connections
(Red and Black).
All four flexible wire tails are
to a
four-way heavy duty terminal block for connection
to the main power cabling. Similarly, the drive unit
is supplied with flexible tails for both the motor
power connection (Red and Black) and the clutch
signal connection (Brown and Blue).
Before commencing power cabling, all
interconnecting terminal blocks should be
screwed into a oosition where they will remain
and protected. When planning the position of the
course computer (ref. 2.1
it is important to
reduce the overall length of heavy power cable
between the drive unit and the vessel’s central
power distribution panel to a minimum. It is
essential
that the copper area of the main power
supply cable is equal to
1
per metre run
between the drive unit and the distribution panel.
For example, a total cable run of 1 Om would
require an interconnecting cable of 1
section area per core.
The power supply must be led from the main
distribution panel and protected by means of a
40 amp fuse or current overload trip switch. A
separate 5 amp fuse must be fitted in the
electronic power supply cable.
It is very important that both the electronic
and heavy duty power supplies are isolated by
a switch in the positive supply line.
When connecting the power supplies to the
main distribution panel and to the course
computer spade connectors, it is essential that
the polarity is correct (Brown positive, Blue
negative).
The drive unit earthing cable (blue) must be
earthed to the
negative
terminal of the vessel’s
power supply with heavy duty cable
This will prevent severe corrosion occurring if
an electrical fault should develop. Normally the
engine is connected to the negative terminal
and may therefore provide a convenient
earthing point.
OUTPUT TO CLUTCH
CIRCUIT
40 AMP-
20 AMP 24V
HEAVY DUTY
POWER SUPPLY
DRIVE UNIT
EARTHING CABLE
