potential could be connected to earth without
that requires manual restarting after voltage failure
disturbing the operation of the circuit in any way.
and for electronic power distribution panels.
MAIN REDUCTION GEAR (MRG). A gear
HERTZ (Hz). A unit of frequency equal to one cycle
arrangement designed to reduce the rpm output of
per second.
the GTE and drive the propeller shaft.
HORSEPOWER (hp). A standard unit of power that
MAIN FUEL CONTROL (MFC). A hydro-
equals 550 foot pounds of work per second.
mechanical device on the propulsion GTE that
HYDRAULIC. Conveyed, operated, or moved by
schedules acceleration fuel flow,
controls
water or other liquid in motion.
deceleration fuel flow, and stator vane angle for
IMPELLER. A blade or series of blades of a rotor that
stall-free, optimum performance over the operating
imparts motion.
range of the GTE.
INTERIM INTEGRATED ELECTRONIC
MAINTENANCE INDEX PAGE (MIP). A basic
CONTROL (IIEC). The IIEC provides the
PMS reference document prepared and issued for
supporting electronic and engine control interface
each installed system/equipment for which PMS
support has been established.
between the GTE and the control consoles.
ISOCHRONOUS MODE. This mode is normally
MAINTENANCE REQUIREMENT CARD
used for generator operation. This mode provides a
(MRC). A card that provides detailed procedures
for performing maintenance requirements and tell
constant frequency for all load conditions. When
who, how, and with what resources a specific
two (or more) generators are operated in parallel,
requirement is to be accomplished.
the isochronous mode also provides equal load
sharing between units.
MARINE GAS TURBINE SERVICE RECORDS.
A comprehensive equipment service record that
JP-5. The primary type of fuel used for helicopters and
provides a history of operation, maintenance, and
small boats. The emergency source of fuel for the
configuration changes to gas turbine equipment.
GTEs and GTGs.
MASKER AIR SYSTEM. This system disguises the
KILOWATT. A unit of electrical power equal to 1000
sound signature of the ship and alters transmission
watts. (A watt is a unit of power equal to the rate of
of machinery noise to the water by emitting air from
work represented by a current of 1 ampere under a
small holes in the emitter rings on the ship's hull.
pressure of 1 volt.)
MEGGER. A high-range ohmmeter having a built-in,
LOAD SHEDDING. Protects a generator from
hand-driven generator as a direct voltage source,
overloading by automatically dropping preselected
used for measuring insulation resistance values and
loads when generator output reaches 100 percent.
other high resistances.
LOCAL CONTROL PANEL (LOCOP). The
MILLIAMPERE. One one-thousandth (.001) of an
LOCOP is the local operating station for the SSGTG
ampere. Abbreviated mA.
on the CG-, DD-, and DDG-class ships. It is located
in the MER near the SSGTG.
MOTOR. A device that moves an object. Specifically,
a machine that converts electric energy into
LOCAL OPERATING PANEL (LOP). The LOP is
mechanical energy.
the local operating station for GTEs on the
FFG-class ships. It is located in the MER and is used
MULTIPLEXING. The process of combining several
primarily for maintenance.
measurements for transmission over the same signal
path.
MACHINERY CONTROL SYSTEM (MCS).
Provides centralized and remote monitoring and
OHM. Symbolized by the Greek letter omega (2). The
control of propulsion, electrical, auxiliary, and
unit of resistance. One ohm is the value of resistance
damage control systems of the DDG-51 class ship.
through which a potential difference of one volt will
maintain a current of one ampere.
MANUAL BUS TRANSFER (MBT). Provides
selection between normal and alternate power
OIL DISTRIBUTION (OD) BOX. This box is located
sources for selected equipment. This transfer switch
at the forward end of each MRG assembly. It directs
is used for controllers with low voltage protection
HP oil from the HOPM to the propeller hub through
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