DOC AIRBUS | AMM A320FTEMPERATURE INDICATING - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL
1. General
The temperature indicating system monitors the APU Exhaust Gas Temperature (EGT). The Electronic Instrument System (EIS) shows on the APU page at the lower ECAM display unit the APU EGT in DEG. C.
** ON A/C NOT FOR ALL The temperature indicating system monitors the APU Exhaust Gas Temperature (EGT). The Electronic Instrument System (EIS) shows on the APU page at the lower ECAM display unit the APU EGT in DEG. C.
** ON A/C NOT FOR ALL
APU Temperature Indicating - Component Location3. System Description
Each thermocouple converts the thermal energy of the APU exhaust gas stream into an electrical voltage. This voltage rises in proportion to the Exhaust Gas Temperature (EGT).
The ECB receives the signals of both thermocouple rakes and evaluates the average temperature value for further processing and indication. In case of 150 deg.F (65.56 deg.C) (for 10 seconds while APU is on-speed) difference between both signals and an APU speed
N > 95% the ECB uses the highest value.
** ON A/C NOT FOR ALL Each thermocouple converts the thermal energy of the APU exhaust gas stream into an electrical voltage. This voltage rises in proportion to the Exhaust Gas Temperature (EGT).
The ECB receives the signals of both thermocouple rakes and evaluates the average temperature value for further processing and indication. In case of 150 deg.F (65.56 deg.C) (for 10 seconds while APU is on-speed) difference between both signals and an APU speed
N > 95% the ECB uses the highest value.
4. Interface
The temperature indicating system has interface with the Control and Monitoring System (Ref. AMM D/O 49-61-00-00).
** ON A/C NOT FOR ALL The temperature indicating system has interface with the Control and Monitoring System (Ref. AMM D/O 49-61-00-00).
5. Component Description
A. EGT Thermocouples
The EGT thermocouple is a chromel-alumel device which has two probes of different lengths. The EGT thermocouples produce a voltage in proportion to the EGT. This voltage is supplied through a shielded cable to the ECB 59KD.
The EGT thermocouple is a chromel-alumel device which has two probes of different lengths. The EGT thermocouples produce a voltage in proportion to the EGT. This voltage is supplied through a shielded cable to the ECB 59KD.
6. Operation/Control and Indicating
The two voltage signals, corresponding to the EGT, are transmitted to the ECB. The ECB evaluates the average between the two signals for control and monitoring the APU operation. In case of 150 deg.F (65.56 deg.C) difference between both signals and an APU speed N > 95% the ECB uses the highest value.
Additionally the computed signal is transmitted via an ARINC 429 bus to the EIS. The APU SYSTEM page on the lower ECAM display unit shows the EGT in deg. C in an analog and a digital display.
The two voltage signals, corresponding to the EGT, are transmitted to the ECB. The ECB evaluates the average between the two signals for control and monitoring the APU operation. In case of 150 deg.F (65.56 deg.C) difference between both signals and an APU speed N > 95% the ECB uses the highest value.
Additionally the computed signal is transmitted via an ARINC 429 bus to the EIS. The APU SYSTEM page on the lower ECAM display unit shows the EGT in deg. C in an analog and a digital display.