NORTHROP GRUMMAN naviguide 4000, User, Installation And Service Manual, Page: 19 / 252

NAVIGUIDE 4000 056336 Rev. AA
1.3: Example System Configurations Page 1–13
1.3.6 FU / NFU Manual Steering for Dual Rudders
Fig.1–6 shows a FU / NFU manual steering system for dual rudder control. This is
basically the F/NN system described in 1.3.1, but with all rudder control facilities
present in twofold.
The hand wheel at the Main Bridge provides synchronous FU control of the port
and stb. rudders.
Each remote steering position is equipped with two FU Mini-Wheel/Display Units
and a Dual Rudder Sync Selector. Once control is transferred to a remote steering
position, the operator may switch from the „Synchronous“ to the „Independent“
mode to control the port and stb. rudders independently.
During normal operation, one of the SCUs will become the bus master and control
all bus communications. The other SCU will become a slave unit. However, in
case of failure of one SCU, the associated rudder can no longer be controlled in
the bus steering modes.
Fig. 1–6:
example FU/
NFU steering
for dual
rudders
Port Wing Main Bridge Stb. Wing
Port
SCU
SAM
Stb.
SCU
Port
Steering
Gear
Pumps
Stb.
Steering
Gear
Pumps
NAVINET 4000 Steering Control Network
DRSS DRSS