pitch control. Under normal conditions, the LOP is not
SCC Maintenance
manned. However, under battle conditions, this console
The SCC on a gas turbine-powered ship has control
is manned and monitored. Since these consoles are
and other electronic circuitry packaged on circuit card
either unmanned or not in control of the plant, any
assemblies inside the consoles. The troubleshooting
malfunction usually shows up on the PACC or the PCC.
techniques you should use for the SCC are the same as
Maintenance of the PLCC and LOP is the responsibility
those for the other consoles we have discussed.
of the GSEs.
Malfunctions to the SCC do not occur as frequently
PLCC and LOP Testing
as they do to other control consoles. However, they do
occur and you must be able to handle any problem that
Testing of the PLCC and LOP is performed by the
arises. Since this console is the responsibility of the
console operator or maintenance person. On DD- and
GSEs, you will be called first to investigate a problem.
CG-class ships, the tests on the PLCC consist of a lamp
Since many different types of systems are controlled
test and audible test of the bell, horn, and siren. On
from the SCC, you must be able to work with other
FFG-7 class ships, the tests on the LOP consist of a lamp
r a t i n g s to solve a problem. For example, if the
test and audible test of the horn and siren. Both the
navigation lights are causing a fault in the SCC, you
PLCC and the LOP have lamp test circuits for testing
must contact the EMs. If there is a malfunction with the
the indicator lamps and LEDs.
ship's heading, a fault in the gyro signal to the SCC may
The audible alarm tests are conducted by depressing
have occurred. In this case, you should call the interior
the appropriate test push button on the PLCC. This
communication electrician (IC) to assist you.
action will cause each audible alarm circuit to sound an
A l w a y s refer to the manufacturer's technical
audible alarm. You will use these audible tests to make
manual when performing maintenance on the SCC. Use
sure the audible alarm circuits are functioning properly.
of the technical manual is essential when you are
T h e lamp test is conducted by activating the
troubleshooting a problem or fault in the SCC. The SCC
STATUS/ALARM switch on the PLCC or depressing a
contains circuits that interact with the circuits in other
LAMP TEST push button on the LOP. This action will
electric and electronic systems. This is why it is
cause the alarm and status lights to illuminate on the
impossible for you to troubleshoot the SCC without
designated section, allowing you to locate the burned
using the technical manual.
out lamps on the console.
PROPULSION LOCAL CONTROL
PLCC and LOP Maintenance
CONSOLE/LOCAL OPERATING PANEL
The PLCC and LOP circuits are similar to those in
The propulsion local control console (PLCC) and
the PACC and PCC. In fact, the troubleshooting and
the local operating panel (LOP) are located in the engine
maintenance procedures used on the PLCC and LOP are
rooms of DD-963, DDG-993, FFG-7, and CG-47 class
the same. Control and other electronic circuitry is
ships. The LOP is found on the FFG-7 class ships.
located on the circuit card assemblies. Each circuit card
T h e PLCC contains the principal electronic
in the PLCC and LOP is assigned its own designation to
equipment necessary for controlling the associated
ease troubleshooting.
propulsion plant. Under normal conditions, the PLCC
Most problems that occur to the PLCC or LOP will
operator does not control the propulsion plant. Instead,
happen during normal operation of the engineering
the transfer electronics is designed to allow the PLCC
plant. The PACC or PCC operator may experience a
operator to take control of the propulsion plant at any
problem that arises from a fault in the PLCC or LOP. As
time. The PLCC normally acts as the receiver of
a GSE, you will be called to investigate such a problem.
propulsion commands from the PACC. The PLCC then
Again, always refer to the manufacturer's technical
processes these command signals and provides the
manual when performing maintenance on the PLCC and
a p p r o p r i a t e output signal to the propulsion plant
LOP.
equipment.
Troubleshooting a problem or fault in the PLCC or
On FFG-7 class ships, the LOP provides a means
for manual operation for maintenance or emergency
the LOP is the same as troubleshooting a fault in the
PACC or PCC. In fact, the PLCC and LOP contain
control and for monitoring each of the GTEs. The LOP
basically the same major circuit function areas as the
also provides throttle control for each GTE and propeller
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