PUMP LOGIC TESTING
Faulty pump
Faulty pump control logic card
Testing the pump logic circuits is usually
a c c o m p l i s h e d with PMS. The MRC gives you
Faulty delay timer or time control card
step-by-step instructions on how to set up your fuel oil
Faulty relay driver card or relay actuator
and lube oil system to complete the test. You accomplish
the test by disconnecting the transducer input from the
Malfunctioning
switches
system and hooking up a gauge comparator to the
If the problem lies within a particular console, you
t r a n s d u c e r . The comparator will simulate system
pressure. Next, you pump up the comparator to reach
must take certain procedural steps to locate the faulty
normal system pressure, and then decrease the pressure
subassembly or circuit card. Use the following steps to
to a predetermined level. Maintain this level for a
troubleshoot console equipment malfunctions:
required number of seconds, after which the pump or
1. Energize the console and related equipment for
pumps will shift speed to maintain pressure. You are
troubleshooting.
checking to see if the pump or pumps will shift up or
down within the required time frame. You should
2. Identify the faulting fictional area.
continue this procedure until all specific operating
3. Refer to the technical manual to locate the signal
points are tested. After completing the test, return the
flow diagram that relates to the faulting functional area.
system to its normal configuration. If the test is not
satisfactory, you will have to start troubleshooting to
4 . Using the proper troubleshooting diagram,
find the problem.
isolate the malfunction to the faulting subassembly or
circuit card.
PUMP LOGIC TROUBLESHOOTING
5. When you have isolated the fault to a particular
c i r c u i t card or subassembly, perform corrective
When a console operator experiences a problem
maintenance by replacing the faulty part.
with pump logic, he or she will contact you, the GSE.
One of your first steps in troubleshooting pump logic
W h e n troubleshooting the pump control logic
circuits is to open the console and check for any fault
circuits, always use proper troubleshooting techniques
LEDs that may be lit. Examination of the circuit cards
and follow all applicable electrical safety precautions.
with lighted LEDs will be your next logical step. Upon
identifying a malfunctioning circuit card, refer to the
proper troubleshooting diagram to identify the faulted
PROPULSION SYSTEM
area.
MAINTENANCE
If there are no faulted circuit cards, you will have to
Most maintenance tasks for the GSE will involve
determine if a problem exists. If the ship is underway
and the system has to be on line, you can not actually
c o n s o l e upkeep and maintenance. The GSE must
work on the problem. While waiting to work on the
remove and replace various parts of the engineering
system, take the opportunity to look at how the system
plant consoles. Each gas turbine-powered ship has
is operating under normal conditions. Take notes on how
several control consoles, each with its own technical
the system is functioning. Your notes should include
manual.
pressures, times, and system configuration. When
In this section, we will discuss the procedures you
system operation is no longer required, you can use the
gauge comparator to duplicate those conditions. Using
will use to perform maintenance on the consoles of
the PMS card, test the pump logic circuits. If the test
several different classes of ships. The basic maintenance
fails, you will need to refer to the manufacturer's
techniques are the same throughout the GSE rating. An
technical manual.
extensive discussion of the maintenance required on
There are several reasons the pump control logic
control consoles is beyond the scope of this TRAMAN.
could malfunction. The following list contains some of
Therefore, the procedures described in this section are
the problems that can cause the pump control logic to
basic in nature. Refer to the proper console technical
fall:
manual for a detailed description of the maintenance
required on your particular propulsion control consoles.
Malfunctioning magnetic controller
5-44
