W DOC AIRBUS | TSM A320F

Failure of the AC Essential Generation Circuit

TASK 24-50-00-810-804-A
Failure of the AC Essential Generation Circuit

1. Possible Causes
  • CNTOR-AC ESS BUS SWITCHING [3XC]
  • wiring
  • GLC-EMER [2XE]
  • RELAY-EMER CONDITION (12XE)
  • CNTOR-AC ESS BUS SWITCHING [15XE]
  • P/BSW-ELEC/AC ESS FEED [11XC]
  • C/B-AC ESS/BUS ON/BUS 1 [1XC]
  • C/B-AC ESS/BUS NORM/CNTOR/CTL [4XC]
  • RELAY-BUS 4XP CTL (3XH)
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
TSM TASK 24-00-00-810-803-A
Circuit Breaker Tripped and/or C/B TRIPPED Warning
AMM 24-24-55-000-001
Removal of the Emergency Generator Line Contactor (EMER GLC)
AMM 24-24-55-000-002
Removal of the AC ESS BUS Contactor
AMM 24-24-55-400-001
Installation of the Emergency Generator Line Contactor (EMER GLC)
AMM 24-24-55-400-002
Installation of the AC ESS BUS Contactor
ASM 242501
AMM 24-25-55-000-001
Removal of the AC Essential Bus Switching Contactor
AMM 24-25-55-400-001
Installation of the AC Essential Bus Switching Contactor
AMM 24-41-00-861-002
Energize the Aircraft Electrical Circuits from the External Power
AMM 24-41-00-862-002
De-energize the Aircraft Electrical Circuits Supplied from the External Power
ASM 245201
AMM 31-60-00-860-001
EIS Start Procedure
3. Fault Confirmation
Subtask 24-50-00-860-056-A
A. Job Set-up
   (1) Aircraft Maintenance Configuration
     (a) Energize the aircraft electrical circuits
AMM 24-41-00-861-002.
Subtask 24-50-00-710-056-A
B. Test
Do the EIS start procedure AMM 31-60-00-860-001.
   (1) If the upper ECAM display unit and the Captain PFD do not operate, do the trouble shooting below:
4. Fault Isolation
Subtask 24-50-00-810-053-A
A. If the test confirms the fault:
  • Release the ELEC/AC ESS FEED pushbutton switch (11XC).
   (1) If the fault disappears:
  • Do a check of the status of the CNTOR 3XC NORM SPLY circuit breaker (4XC).
     (a) If the circuit breaker (4XC) is closed:
  • Push the ELEC/AC ESS FEED pushbutton switch (11XC) and do a check for 115VAC between the pins B/K and B/L of the contactor (3XC) ASM 242501.
       1 If there is 115VAC:
       2 If there is not 115VAC:
  • Do a check for 115VAC at the pin 2 of the circuit breaker (4XC).
         a If there is 115VAC:
         b If there is not 115VAC:
  • Do a check of the status of the AC ESS/BUS ON/BUS 1 circuit breaker (1XC).
         c If the circuit breaker (1XC) is closed:
  • Do a check and repair the wiring between the pins A2, B2, C2 of the circuit breaker (1XC) and the pins L1, L2, L3 of the contactor (3XC), then from the pin L3 of the contactor (3XC) to the pin 1 of the circuit breaker (4XC) ASM 242501.
         d If the circuit breaker (1XC) is open:
         e If the fault continues:
  • Replace the C/B-AC ESS/BUS ON/BUS 1 [1XC] .
     (b) If the circuit breaker (4XC) is open:
       1 If the fault continues:
  • Do a check of the wiring for short to ground between respectively:
    . the pin 2 of the circuit breaker (4XC) and the pin B/R of the contactor (3XC)
    . the pin 2 of the circuit breaker (4XC) and the pin B/K of the contactor (3XC), through all the components given in Para. 4.A.(1)(a)2_a_ ASM 242501.
         a If the wiring is not correct:
  • Repair the wiring .
         b If the wiring is correct:
  • Replace the C/B-AC ESS/BUS NORM/CNTOR/CTL [4XC] .
   (2) If the fault continues:
  • Replace the RELAY-BUS 4XP CTL (3XH).
     (a) If the fault continues:
  • Replace the RELAY-EMER CONDITION (12XE).
     (b) If the fault continues:
  • Replace the P/BSW-ELEC/AC ESS FEED [11XC] .
     (c) If the fault continues:
  • Do a check of the wiring for short to ground between the C/B (2XH) and the pin A/X of the relay (3XH) ASM 245201.
       1 If the wiring is not correct:
  • Repair the wiring .
       2 If the wiring is correct:
  • Do a check and repair the wiring between the pins K1, K2, K3 of the contactor (3XC) and the first branch point ASM 242501.
       3 If the fault continues:
Subtask 24-50-00-710-057-A
B. Do this test to make sure that the system operates correctly:
5. Close-up
Subtask 24-50-00-860-057-A
A. Put the aircraft back to its initial configuration.
   (1) On the ECAM control panel, set the UPPER DISPLAY and LOWER DISPLAY potentiometers to OFF.
   (2) De-energize the aircraft electrical circuits
AMM 24-41-00-862-002.
[Rev.8 from Aug 2018] 2026.04.04 04:26:56 UTC
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