Although the MCS and DMS are different from the
The audible alarm test is conducted by depressing
control systems on other gas turbine-powered ships, the
the BELL push button on the BCU. This action causes
basic troubleshooting and maintenance procedures are
the audible alarm circuits to sound the bell alarm. The
the same. Control and other electronic circuitry is
volume of the audible alarm is adjusted by a variable
located on circuit card assemblies. As the maintenance
potentiometer located to the right of the test pushbutton.
p e r s o n , you must read the technical manual to
The operator or maintenance person uses this test to
thoroughly understand the interfaces. Always refer to
make sure the audible alarm circuit is functioning
the manufacturer's technical manual when performing
properly.
maintenance on the SCU.
T h e lamp test of the BCU is conducted by
Again, use of the technical manual is essential when
depressing the TEST push button on the throttle control
you are troubleshooting a problem or fault in the SCU. This
panel. When the push button is depressed, all lamps on
console contains circuits that interact with the circuits in
the BCU light. You will use this test to make sure the
other electronic systems and the propulsion equipment. It
lamp circuits are functioning properly.
is therefore impossible for you to troubleshoot the SCU
without using the technical manual. Troubleshooting a
BCU Maintenance
problem or fault in the SCU is the same as troubleshooting
a fault in the other MCS consoles.
The BCU uses the MCS to monitor and control the
propulsion system from the bridge. It also uses the DMS
to communicate with other consoles. Planned
BRIDGE CONTROL UNIT
maintenance is conducted on the BCU by using the
proper MRCs. The troubleshooting and maintenance
A bridge control unit (BCU) is located in the
procedures used on the BCU are the same as those used
p i l o t h o u s e on the DDG-51 class ships. The BCU
on other MCS consoles. Always refer to the
provides control of the thrust of the port and starboard
manufacturer's technical manual when performing
shafts from the SCC in the pilothouse. The BCU also
maintenance on the BCU.
provides the switches and indicators for transferring the
p r o p u l s i o n control station location between the
Use of the technical manual is essential when you
pilothouse, the CCS, and the engine rooms. The BCU
are troubleshooting a problem or fault in the BCU. This
also provides on and off control of the washdown
console contains circuits that interact with the circuits
countermeasures groups 1 through 4.
i n other electronic systems and the propulsion
equipment. You can not effectively troubleshoot the
S e v e r a l components mounted in the SCC are
BCU without using the technical manual.
considered to be a part of the BCU. They are the +5 and
15 volt dc power supply, a tone generator, a speaker
GENERAL CONSOLE MAINTENANCE
assembly, and a cable entry assembly. The power supply
is used to supply +28 volts dc and +5 volts dc to the BCU
The consoles on gas turbine-powered ships differ in
assemblies. The tone generator and speaker are used to
style, construction, and operation. However, there are
generate the audible alarms for the MCS at the SCC. The
some general maintenance procedures that apply to all
cable entry assembly provides the cable connectors for
control consoles. As a GSE, you will have to recognize
interfacing ship's cables with the BCU.
a symptom and associate it with the proper functional
Since the SCC controls the operation of the ship, the
a r e a . This technique will help you start your
c o r r e c t operation of the BCU is essential. The
troubleshooting in the correct area. Although the fault
malfunctions that occur to the BCU are immediately
might not be in that particular area, you will at least not
reported. Because maintenance of the BCU is also the
overlook that possibility. For this reason, you must know
responsibility of the GSEs, you, the GSE, will be called
the purpose of each circuit group and how it functions.
to correct the problem.
Console Circuits
BCU Testing
Each control console contains several types of
The BCU is tested by the console operator or
c i r c u i t s that you must be familiar with before
maintenance person. The tests on the BCU consist of a
p e r f o r m i n g maintenance on them. Although these
lamp test of the indicators and an audible alarm test of
circuits contain the same components, they operate
the bell.
differently. The basic purposes of the circuits inside the
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