Another area of the electrohydraulic control system
When trouble occurs, examine the system, determine
that deserves your concern is the pitch indicating
the cause, and record your findings.
system. If pitch readings on the remote consoles do not
Whenever you are troubleshooting pitch control
match the actual mechanical pitch settings, then trouble
systems, using the appropriate manufacturer's
exists in the pitch indicating system. The circuits used
t r o u b l e s h o o t i n g guide is essential. This guide is
to produce and display these indications are different on
provided as an aid to troubleshooting and correcting
the various types of gas turbine ships. The methods you
faults that may occur in the propeller pitch system.
w i l l use for troubleshooting the pitch indicating
The troubleshooting guide contains a description of
systems, however, are the same. The safety precautions
symptoms noticeable to the operator along with a list
you should observe and the equipment you should use
of possible causes. Using this guide allows you to
for troubleshooting are the same.
direct your attention to a specific component. Being
Once again, the most important tools in trouble-
able to identify both the type of malfunction and the
shooting the CRP/CPP systems are the
faulty component will allow you to make a logical
m a n u f a c t u r e r ' s technical manual and the trouble-
decision to repair, replace, or investigate further.
shooting guide. Remember, if you are troubleshooting
Remember, a complete loss of control is most often
the pitch indicating system, you will also have to use
c a u s e d by two malfunctioning components acting
t h e technical manual for each specific console
together. Either component alone might not cause any
involved.
noticeable impairment of operation. Repairing one
component may restore operation, however, it may
also set the stage for a recurrence should a second
MOTOR AND GENERATOR
malfunction be present.
MAINTENANCE
W h e n troubleshooting CRP/CPP systems, you
Another important job of the GSE is the maintenance
should use the most effective method. This method
of the motors and generators located in the main engine
includes the following steps:
room. This maintenance includes keeping the motors and
generators clean and troubleshooting any faults that occur.
1. Communicate with the personnel on watch when
Faults with the brushes, brush rigging, and bearings are
the system was performing correctly.
normally the extent of the repairs performed by the GSE.
2. Communicate with the personnel on watch when
Larger and more extensive repairs, such as rewinding,
trouble with the system first occurred.
insulating, varnishing, and balancing, are accomplished by
tenders, shipyards, and sometimes by the electrician's
3. Determine if corrective or scheduled main-
mate (EM) on board your ship.
tenance was accomplished before the trouble was
reported.
MAINTENANCE PROCEDURES
T r o u b l e s h o o t i n g the electrohydraulic control
systems of different classes of ships is practically the
The essential points in the maintenance of electric
same. All systems contain an electrohydraulic servo
generators and motors include the following steps:
control valve. As a GSE, your troubleshooting efforts
1. Keep the insulation clean and dry and make sure
will be concentrated in this area. If your ship experiences
it has high resistance.
erratic, slow, or no pitch response to normal commands,
then you should suspect the electrohydraulic servo
2. Keep all electrical connections tight.
control valve. The following list contains some of the
3 . Keep the machines in good mechanical
steps you can take to locate the exact cause of the failure:
condition.
1. Check for the voltage to the electrohydraulic
We will discuss each of these steps in the following
servo control valve.
paragraphs.
2. Check the electrohydraulic servo control valve
falter for cleanliness.
Cleanliness
3. Check the electrohydraulic servo control valve
Keeping the interior and exterior of motors and
solenoid for proper operation.
generators clean and free from dirt and debris is
4 . Check the control circuitry of the electro-
important. Dirt, salt, lint, oil, water, and especially
hydraulic control system.
carbon or copper dust, all present hazards to motors and
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