(3)
Engine over-temperature operation is indicated by a red warning light in the indicator dial face which illuminates when the engine is at, or above, the red line limit.
(4)
The intensity of the LED digital display is controlled by an ambient light sensitive cell mounted in the dial face.
C. AIRPLANES WITH EIS; The EGT indicator is shown on the primary engine display as a simulated electro-mechanical device.
4. Operation
_________
A. The power for the EGT indicating system is 28v dc provided by EIS or EGT IND circuit breakers on panel P6.
B. The thermocouple probes cause a voltage that is proportional to the temperature around the chromel-alumel hot-junction. Parallel chromel-alumel leads connect the probes to the junction boxes. The junction boxes give an average of the voltages. The EIS or the EGT indicator reads this average of the voltages.
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ALL ú ú C06 Page 4 ú Nov 12/00
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
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A / /
CFM56 ENGINES
737-300/400/500/ /
MAINTENANCE MANUAL ////////////////////////
PULL
TO
SET
N1
ENGINE 1
EGT Indicating System Simplified Schematic Figure 3 (Sheet 1)
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AND 9 PROBE EGT SYSTEM ú ú C06 Page 5 ú Jul 15/95
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
////////////////////////A / /
CFM56 ENGINES
737-300/400/500/ /MAINTENANCE MANUAL ////////////////////////
28V DC EGT IND P6 LOAD CONTROL CENTER
ENGINE
ENGINE 1 AND 2
EGT Indicating System Schematic Figure 3 (Sheet 2)
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ú ú C03 Page 6 ú Jul 15/95
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
////////////////////////A / /
CFM56 ENGINES
737-300/400/500/ /MAINTENANCE MANUAL ////////////////////////
EGT Indicating System Schematic
Figure 3 (Sheet 3)
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ú ú C03 Page 7 ú Jul 15/95
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
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CFM56 ENGINES
737-300/400/500/ /MAINTENANCE MANUAL ////////////////////////
C. AIRPLANES WITHOUT EIS; The thermocouple amplifier, in the EGT indicator, reads the average of the voltages. The multiplexer digitizes the signal and compares this digital signal to the digital signal of the cold junction reference. The processor module reads the output of the multiplexer and gives the applicable signals to these modules: the digital display, the pointer, and the light that shows if the EGT is more than the limit.
D. AIRPLANES WITH EIS; The precision amplifier, in the EGT indicator, reads the average of the voltages. The precision amplifier also compares this signal to the to the signal of the cold junction reference. The microprocessor reads the output of the precision amplifier and gives the applicable signals to these modules: the digital display, the pointer, and the light that shows if the EGT is more than the limit.
(1)
The Slope Adjust, Datum Adjust and Gain Adjust are analog inputs that are preset to compensate for ambient temperature effects and gain and offset effects in the thermocouple amplifier, thus giving a processor module that is interchangeable between EGT indicators.
(2) 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：737-300 400 500 AMM 飞机维护手册 发动机指示 ENGINE INDICATIN(16)
