POWER SUPPLY. A unit that supplies electrical
the shaft bore. The OD box also establishes
power to another unit. It changes ac to dc and
propeller pitch by using control oil from the HOPM
maintains a constant voltage output within limits.
to position the valve rod, which extends through the
shaft to the hub.
POWER TURBINE (PT). The GTE turbine that
converts the GG exhaust into energy and transmits
OPEN CIRCUIT. A circuit which does not provide a
the resulting rotational force via the attached output
complete path for the flow of current.
shaft.
ORIFICE. A circular opening in a flow passage that
PRAIRIE AIR SYSTEM. This system emits cooled
creates a flow restriction.
bleed air from small holes along the leading edge of
PARAMETER. A variable, such as temperature,
the propeller blades. The resulting air bubbles
pressure, flow rate, voltage, current, or frequency
disturb the thrashing sound so identification of the
that may be indicated, monitored, checked, or
type of ship through sonar detection becomes
sensed in any way during operation or testing.
unreliable.
PERMANENT MAGNET ALTERNATOR (PMA).
PRESSURE. Force per unit of area, usually expressed
The PMA is mounted on the generator shaft
as psi.
extension of each GTGS and supplies speed sensing
PRESSURE SWITCH. A switch actuated by a change
and power to the electronic governor. The PMA also
in the pressure of a gas or liquid.
supplies initial generator excitation.
PRESSURE TRANSDUCER. An instrument which
PHASE. (1) The angular relationship between current
converts a static or dynamic pressure input into the
and voltage in ac circuits. (2) The number of
proportionate electrical output.
separate voltage waves in an ac supply (e.g.,
single-phase, three-phase, etc.).
PRIME MOVER. (1) The source of motion-as a GTE,
(2) the source of mechanical power used to drive a
PHOTOELECTRIC. Electricity produced by the
pump, or compressor, (3) or rotor of a generator.
action of light.
PROPELLER A propulsive device consisting of a
PITCH. A term applied to the distance a propeller will
boss or hub carrying two or more radial blades.
advance during one revolution.
(Also called a screw.)
PLASMA DISPLAY UNIT (PDU). An orange-
PROPULSION AUXILIARY CONTROL
colored backlit display screen mounted in the panel
CONSOLE (PACC). This console is located in
face of the MCS consoles. Typed data in
CCS and is part of the PAMCE. It contains the
alpha-numeric format is printed on the interior
electronic equipment capable of controlling and
plasma face of the unit. It is used to present
monitoring both propulsion plants and auxiliary
equipment status data to operators for information
equipment on a CG-47, DD-963, or DDG-993 class
or action.
ship. (Also known as PACC on the DDG-51 class
PMS FEEDBACK REPORT. A form ships use to
ship but not a part of PAMCE.)
notify the Naval Sea Support Center or the Type
PROPULSION AND AUXILIARY MACHINERY
Commander of matters related to PMS.
CONTROL EQUIPMENT (PAMCE). This
POTENTIOMETER. A variable resistance unit
equipment is located in CCS, is part of the ECSS,
having a rotating contact arm that can be set at any
and includes the PACC and PACEE. This equipment
desired point along the resistance element.
provides centralized control and monitoring of both
POWER. The rate at which work is done. Units of
main propulsion plants and auxiliary machinery on
power are: the watt, the joule, and the kilowatt.
a CG- or DD-class ship.
POWER LEVEL ANGLE (PLA). A rotary actuator
PROPULSION AND AUXILIARY MACHINERY
mounted on the side of the GTE fuel pump and its
INFORMATION SYSTEM EQUIPMENT
(PAMISE). This equipment is located in CCS and
output shaft lever. It is mechanically connected to
is part of the ECSS. This equipment receives,
the MFC power lever. The PLA actuator supplies
the torque to position the MFC power lever at the
evaluates, and logs the engineering plant
commanded rate.
performance, status, and alarm state. The PAMISE
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