alphabetic, 3 ½ -numeric character digital display and a
39 segment bar graph display. The bar graph display
is nonlinear. The indicator has a digital display range
of 0 to 110.0% RPM while displaying current N1 and 0
to 199.9% RPM while displaying exceedence N1. The
bar graph display range is 0 to 105.0% RPM.
The digital display shall contain dashes (------)
when the measured N1 is greater than 110.0% RPM.
When displaying EXCEEDENCE N1 values, the actual
measured value, not "-----", shall be displayed, up to
The indicator shall perform BIT on the LCD
display, ROM, RAM, EEPROM, and input signal. The
display BIT will consist of displaying all active LCD
segments for 3 seconds on power up. If the ROM or
RAM fails BIT the indicator display will be blank. If the
input signal fails BIT the indicator will display 0 on both
the digital and bar graph displays. If the EEPROM BIT
fails the indicator will prefix the digital display with F.
BIT failures shall not be stored in EEPROM. Failures
detected will not affect the display after power is
cycled unless the failure is again encountered.
Exceedence events will be stored in EEPROM
memory. Each event record will consist of two 16-bit
words. One word will contain the peak percent RPM
measured during the event and the other word shall
contain the event duration in seconds. A maximum of
50 events shall be recorded. If more than 50 events
are recorded, only 50 shall be stored. As new events
are recorded, the oldest events shall be discarded.
The indicator shall prefix the digital display with
an E when an event is being or has been recorded and
not played back. The indicator will start recording an
event immediately when the indicator has measured
percent RPM greater than 102.6 or when the indicator
has measured percent RPM above 101.5 continuously
for 10 seconds. The indicator will end recording and
store the event when the measured percent RPM
drops to 101.5 or lower.
Pressing the EXCEEDENCE ERASE switch
for longer than 0.2 seconds will cause all
events to be erased from non-volatile
memory. There are no provisions for
erasing individual events.
EXCEEDENCE DISPLAY switch for 0.2 seconds or
longer. Each event display will consist of the following
1. The event number will be displayed
for 2 seconds.
2. The event peak percent RPM shall be
displayed for 2 seconds.
3. The event duration, in seconds, will be
displayed for 2 seconds.
All three data items displayed during playback
shall be prefixed with a P unless an EEPROM BIT
failure has been detected in which case the display will
be prefixed with an F.
Once an event playback sequence has been
performed, the E prefixed to the digital display will be
removed. All event data is still available for playback
until the data is erased. The display will be prefixed
with an E again on the next power up cycle if the old
data has not been erased or if another event is
(4) Engine Oil Pressure and Temperature
Indicator. The indicator displays the measured engine
oil pressure and engine oil temperature on two
separate 23-segment nonlinear bar graph displays.
The oil pressure indicator has a bar graph display
range of 0 to 200 psi. The engine oil temperature
portion of the gauge has a range of 0 to 120 C. The
segment display resolution for the oil pressure is 20
psi in the 0 to 60 psi range, 5 psi in the 60 to 140 psi
range, and 20 psi in the 140 to 200 psi range.
The indicator has a BIT on the LCD display,
ROM, RAM, and the signal input path. The display
BIT consists of displaying all active LCD segments for
3 seconds on power up. If the ROM or RAM BIT fails
the indicator display will be blank. If the input signal
fails BIT the indicator shall display 0 psi.
(5) Fuel Flow Indicator. The indicator shall
display the measured fuel flow concurrently in a 1
alphabetic, 3 ½ -numeric character display and a
41-segment bar graph display.
The indicator has a digital display range of 0 to
600 pounds per hour. The bar graph displays a range
of 0 to 600 pounds per hour. The digital display will
contain dashes (------) when the measured fuel flow is
greater than 600 pounds per hour.
The indicator shall perform BIT testing on the
LCD display, ROM, RAM, and the signal input path.
The display BIT consists of displaying all active LCD
segments for 3 seconds on power up. The signal input
BIT verifies the range of the incoming signal. If the
ROM or RAM fails BIT the indicator display will be
blanked. If the input signal fails BIT the indicator shall
display "0" on both the digital and bar graph display.