5 . Alarm acknowledge and flasher/siren-bell
consoles are described in the following paragraphs. As
inhibit (silencing) circuits
always, refer to the manufacturer's technical manual for
a detailed description of the circuits in a particular
6. Audible alarm tone generator and associated
control console.
speakers
CONTINUOUS DISPLAY CIRCUITS.-- A
7. SEM logic assemblies
continuous display circuit consists of the
Typically, signals originate at the sensors and
edgewise-reading meters and their related wiring. These
transducers located at the device where the function is
meters continuously monitor and display parameters of
being monitored. From the sensors, some of the signals
the ship's propulsion and associated systems. Each
are wired directly to the consoles. Some signals are
console has meter-monitor functions that are displayed
r o u t e d through other circuits for timing, signal
on a different number of meters on the console. Some
conditioning, and threshold detection. Still other signals
meter-monitor functions are displayed on dual
are routed through a computer. The results of these
(side-by-side) scale meters, while others are displayed
signals are then wired to the consoles.
on single-scale meters. Whether dual- or single-scale,
all meter movements are electrically the same. Each
DEMAND DISPLAY CIRCUITS.-- The demand
meter has a specific volts dc movement with a specific
display circuits consist of the demand-display controls
percentage of accuracy and internal resistance. The
and indicators on the consoles. The circuits also include
meters on the consoles of the DDG-51 class ships are
the interconnecting wiring and the interfaces with the
LED-type meters and function differently from the
serial data or MCS components. Demand display is
meters on the other classes of gas turbine-powered
accomplished through the plasma display unit on the
ships. The signals to these meters are controlled by the
DDG-51 class ships. Demand display on the other gas
AN/UYK-44 computer. The meter faces are marked and
t u r b i n e - p o w e r e d ships is accomplished through
scaled for the parameter displayed. The meters can be
thumbwheel-type decimal display rotary switches.
mechanically or electrically zeroed.
CONTROL CIRCUITS. The control circuits are
STATUS DISPLAY CIRCUITS. The status
t h o s e circuits that are operator initiated through
d i s p l a y s consist of various indicator lamps and
switching devices, such as switch-indicators,
switch-indicators on the console control and display
p u s h - b u t t o n switches, and thumbwheel switches.
p a n e l s . Each of the panels contains one or more
C o n t r o l signals initiated by switch-indicators are
indicators or switch-indicator assemblies. Regardless of
usually momentary in nature. These signals are applied
the indicator type, each indicator lamp is operated on
through some type of debounce, latching, or control
and off by the application or removal of a dc voltage.
logic circuit before being sent through the serial data or
This dc voltage is applied or removed by some type of
DMS to the function to be controlled. Push-button
lamp driver circuit associated with the circuit. On the
initiated control signals are also momentary but are
DDG-51 class ship, SEMs transfer data to the computer
usually applied directly to the associated logic circuits.
for status display. The indicators and switch-indicator
Rotary-switch-initiated control signals are usually
lenses provide white and various colored backgrounds
discrete types and are buffered before being applied to
when lighted. This highlights the engraved legends of
t h e logic circuits. Thumbwheel-generated control
the lenses.
signals are also buffered and are routed through the
A L A R M DISPLAY CIRCUITS. The alarm
serial data system to the functions they control.
display and associated audible warning circuits of each
S E R I A L DATA CIRCUITS. The serial data
console are shown in the flow and schematic diagrams
circuits consist of a serial transmitter circuit, a serial
in the appropriate technical manuals. The alarm display
receiver circuit, and an automatic self-test circuit. The
circuits may consist of the following:
serial transmitter circuit multiplexes parallel data,
1. Alarm control logic cards or modules
converts it into serial data, and transmits it via the serial
data bus. The serial receiver circuit receives serial data
2. Lamp driver cards or modules
from the serial data bus, converts it to parallel data, and
3. Alarm indicator lamp assemblies
buffers it to other console circuits. The self-test circuit
performs a continuous automatic self-test of serial data
4. Alarm summary and audible alarm selection
cards.
logic (horn, siren, or buzzer)
5-54
