(d)
If a previous (before the most recent) N1 RED exceedance does not exist, the upper readout will be blank.
(3)
Exhaust Gas Temperature Redline Limit Exceedance (EGT RED)
(a)
EGT RED exceedance information is displayed for engines 1 thru 4 by white colored digital readouts. The display consists of one exceedance and time duration value for each engine.
(b)
The readout displays the highest EGT of all previous EGT RED exceedances (excluding the most recent), and the time duration of that exceedance.
(c)
Information pertaining to the most recent EGT RED exceedance is found in the EGT RED profile.
(4)
Exhaust Gas Temperature Start Limit Exceedance (START)
(a)
EGT START exceedance information is displayed for engines 1 thru 4 by white colored digital readouts. The display consists of one exceedance and time duration value for each engine.
(b)
The readout displays the highest EGT of all previous START exceedances (excluding the most recent) and the time duration of that exceedance.
(c)
Information pertaining to the most recent START exceedance is found in the EGT START profile.
(5)
N2 Redline Limit Exceedance (N2 RED)
(a) N2 RED exceedance information is displayed for engines 1 thru 4 by white colored digital readouts. The display consists of two exceedance and time duration values (upper and lower) for each engine.
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(b)
The lower readout displays the highest N2 which occurred during the most recent N2 RED exceedance, and the time duration of that exceedance.
(c)
The upper readout displays the highest N2 of all previous N2 RED exceedances (excluding the most recent) and the time duration of that exceedance.
(d)
If a previous (before the most recent) N2 RED exceedance does not exist, the upper readout will be blank.
(6) EGT Profiles
(a)
There are two types of EGT profiles: EGT start cycle exceedances (EGT START) and EGT operational exceedances (EGT AMBER/RED).
(b)
Eleven predefined temperature levels are stored in the memory of the EIU for each profile type (22 levels in all). These temperature levels are used to form the EGT profiles. 1) During an engine start cycle, if actual EGT exceeds the
lowest predefined start cycle temperature level, an EGT START profile is processed.
2) For the EGT operational profile, the exceedance begins as an EGT amber band limit exceedance (EGT AMBER). This profile will automatically change to a EGT redline limit exceedance (EGT RED) once the redline limit is exceeded. When this occurs, the EGT profile identifier caption changes from EGT AMBER to EGT RED.
(c)
The predefined temperature levels are not available for display in the form of a profile until the actual EGT has exceeded the lowest predefined temperature level and then returned below this lowest level. Once the actual EGT has returned to below the lowest predefined temperature level, all the levels which were exceeded are simultaneously displayed as an engine exceedance EGT profile.
(d)
The lowest predefined temperature is displayed at the bottom of the left-hand column and highest predefined temperature is displayed at the top. The temperature which is displayed above the highest predefined temperature and below the ENG caption is the highest temperature obtained during the exceedance (this is an actual temperature value, not a predefined temperature level).
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(e)
The total time that the actual EGT exceeded each predefined temperature level is displayed adjacent to the level in the right-hand column of the profile.
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