NORTHROP GRUMMAN naviguide 4000, User, Installation And Service Manual, Page: 26 / 252

056336 Rev. AA NAVIGUIDE 4000
Page 2–2 2.1: General Concepts
2.1.2 Engaging / Disengaging Bus Steering
When bus steering is engaged, the outputs of the SCU(s) are connected to the
steering gear and the rudder angle(s) are controlled through the SCU(s).
When bus steering is disengaged, the outputs of the SCU(s) are disconnected
from the steering gear and the rudder(s) are controlled directly through NFU tillers
or other control devices.
Depending on the bus devices present, one or more of the steering modes „FU“
(or „Helm“), „Auto“, „Nav“, „Track“ and „External“ are available when bus steering
is engaged. Depending on the selected steering mode, the SCU(s) receive the
rudder order from manual FU control devices, from the NAVIPILOT 4000 heading
control system, or from an external system.
Fig. 2–1:
Steering gear
control in non-
bus and bus
steering
modes
Steering
Gear
Non-Bus Steering Modes
Bus Steering Modes
Follow-Up (FU)
Non Follow-Up (NFU)
Auto
External
External
System
SCU