C. Self Test The BITE of the ECB does a self test of the APU systems with the APU off line (not in operation) through an ARINC 429 bus. The BITE examines all the internal ECB and external APU circuits. A record of LRU failures is transmitted to the CFDS. A self test is also used to make sure that the system is satisfactory after maintenance action has been taken. The self test cannot occur when the APU speed is more than 7 %. The self test takes approximately 3 s.
D. Table of LRUs examined through the BITE of the ECB in different test modes.
Table 1a ............ BITE coverage of ECB hardware elements
------------------------------------------------------------------------------NO | ECB HARDWARE ELEMENTS | TEST MODE | | | PUT | SET | IOT | -------+----------------------------------------------+-------+-------+------+ 1 | CPU and internal data bus | covered by item 2 | 2 | RAM | X | | | 3 | EPROM | X | | | 4 | EEPROM | X | X | X | 5 | ECB configurations | X | | | 6 | ARINC circuits | X | | | 7 | Watchdog circuit | X | | | 8 | A/D conversion | X | X | X | 9 | D/A conversion | X | X | X | 10 | Analog input conditioner | X | X | X | 11 | Cold junction temperature | X | X | X | 12 | Pressure sensor supply | X | X | X |
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NO | ECB HARDWARE ELEMENTS | TEST MODE | | | PUT | SET | IOT | -------+----------------------------------------------+-------+-------+------+ 13 | LVDT excitation | X | X | X | 14 | Overspeed governor (references) | X | X | X | 15 | Overspeed governor (overspeed protection) | | | X | 16 | Frequency input conditioner | | | X | 17 | Power supply unit | X | X | X | 18 | A/C relay driver | covered by load test | 19 | Start contactor driver (main/backup) | covered by load test | 20 | APU available driver | covered by load test | 21 | Start in progress driver | covered by load test | 22 | Fault relay driver | covered by load test | 23 | LCV position signal driver | covered by load test | 24 | Low fuel pressure valve driver | covered by load test | 25 | De-oil solenoid driver | covered by load test | 26 | Ignition unit driver | covered by load test | 27 | Fuel solenoid driver | X | X | X | 28 | LCV solenoid driver | covered by load test | 29 | Flap open command driver | covered by | 30 | Flap close command driver | inlet flap test | 31 | Fuel torque motor driver | covered by motor test| 32 | IGV torque motor driver | covered by motor test| 33 | SCV torque motor driver | covered by motor test| | | | | |
Table 1b ............ BITE coverage of Sensors
------------------------------------------------------------------------------NO | SENSORS | TEST MODE | | | PUT | SET | IOT | -------+----------------------------------------------+-------+-------+------+ 1 | Delta pressure | X | X | X | 2 | Inlet (ambient) presure | X | X | X | 3 | Total pressure | X | X | X | 4 | EGT 1 | X | X | X | 5 | EGT 2 | X | X | X | 6 | LCIT | X | X | X | 7 | LCDT | X | X | X | 8 | Oil sump temperature | X | X | X | 9 | Generator oil temperature | X | X | X | 10 | Speed monopole 1 (open wire and amplitude) | X | X | X | 11 | Speed monopole 2 (open wire and amplitude) | X | X | X | 12 | IGV LVDT (open wire and position) | X | X | X | 13 | LCV (position) | | | X |
Table 1c ............ BITE coverage of Switches
------------------------------------------------------------------------------NO | SWITCHES | TEST MODE | | | PUT | SET | IOT | -------+----------------------------------------------+-------+-------+------+ 1 | Aircraft identification | X | X | | 2 | LCV activation | X | X | | 3 | Low oil quantity | X | X | | 4 | LCV open | X | X | | 5 | LCV closed | X | X | | 6 | Oil filter clogged (switch) | | | X | 7 | High oil temperature | X | X | | 8 | Flap open | | | X | 9 | Flap close | | | X |
Table 1d ............ BITE coverage of Actuators/Indicators
------------------------------------------------------------------------------NO | ACTUATORS/INDICATORS | TEST MODE | | | PUT | SET | IOT | -------+----------------------------------------------+-------+-------+------+ 1 | Fuel torque motor | X | X | X | 2 | IGV torque motor | X | X | X | 3 | SCV torque motor | X | X | X | 4 | Starter motor | X | X | X | 5 | A/C relay | X | X | X | 6 | Start contactor (main/backup) | X | X | X | 7 | APU available | X | X | X | 8 | Start in progress | X | X | X | 9 | Fault relay | X | X | X | 10 | LCV position signal | X | X | X | 11 | Low fuel pressure valve | X | X | X | 12 | De-oil solenoid | X | X | X | 13 | Ignition unit | X | X | X | 14 | Fuel solenoid | X | X | X | 15 | LCV solenoid | X | X | X | 16 | Flap open actuator | X | X | X | 17 | Flap close actuator | | | X |
Table 1e ............ BITE coverage of ARINC Transmitters
------------------------------------------------------------------------------NO | ARINC TRANSMITTERS | TEST MODE | | | PUT | SET | IOT | -------+----------------------------------------------+-------+-------+------+ 1 | Centralized Fault Display Interface Unit | | | X | 2 | Environmental Control System | | | X | 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：A320飞机维护手册 AMM 机载辅助动力 AIRBORNE AUXILIARY POWER5(151)
