NORTHROP GRUMMAN naviguide 4000, User, Installation And Service Manual, Page: 78 / 252

056336 Rev. AA NAVIGUIDE 4000
Page 4–2 4.2: Electrical Installation
4.2 Electrical Installation
4.2.1 Wiring
Each NAVIGUIDE 4000 system is delivered with installation-specific connection
drawings.
Wire up the NAVIGUIDE 4000 system according to the connection drawings pro-
vided. Do not yet energize the system.
4.2.2 NAVINET 4000 Steering Control Network
NAVINET 4000 is a 120
Ω
controlled impedance bus.
The bus is divided into two sections: the backbone, and the stubs which connect
to individual nodes (SCUs and bus interface units). The length of each stub must
not exceed 3 metres. At a data transfer rate of 250 kbps, the maximum backbone
length is 160 metres.
The internal bus power supply of the SCU supports up to 10 nodes. If more than
10 nodes are contained in the system, check that an external bus power supply is
provided and properly connected.
All nodes must be configured to the same baud rate for the bus to operate prop-
erly. At the time of writing of this manual, NAVINET 4000 supports a data transfer
rate of 250 kbps.
4.2.2.1 Approved cable type
NAVINET 4000 requires a bus backbone cable which is approved for compatibil-
ity with the requirements of the CAN bus according to IEC 61126-3.
At the time of writing of this manual, the only approved type of cable is the Lapp
2705250 Unitronic Bus DeviceNet™ Trunk cable, manufactured by U.I.Lapp,
Schultze-Delitsch Str. 25, D-70565 Stuttgart, Germany.
As the backbone cable is shipyard/owner supply, it must be verified that the abobe
mentioned type of cable is provided. Bus communications will not operate reliably
over other types of cable.
Caution
The function of the NAVIGUIDE 4000 system critically depends on the correct in-
stallation of the NAVINET 4000 Steering Control Network bus.