W DOC AIRBUS | TSM A320F

Failure of the AC BUS 1 with the APU Generator in Operation

TASK 24-50-00-810-809-A
Failure of the AC BUS 1 with the APU Generator in Operation

1. Possible Causes
  • BTC-1 [11XU1]
  • wiring
  • RELAY-EPC AUX CTL [5XG]
  • RELAY-GLC 1 AUX CTL [4XU1]
  • GLC-1 [9XU1]
  • RELAY-BUS TIE [30XU1]
  • C/B-ELEC/GEN1/OFF/BTC1 SPLY [5XU]
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
ASM 242202
AMM 24-22-34-000-001
Removal of the GCU-1(2)
AMM 24-22-34-400-001
Installation of the GCU-1(2)
AMM 24-22-55-000-001
Removal of the Contactors
AMM 24-22-55-400-002
Installation of the Contactors
ASM 242302
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
AMM 31-60-00-860-001
EIS Start Procedure
3. Fault Confirmation
Subtask 24-50-00-860-064-A
A. Job Set-up
   (1) Aircraft Maintenance Configuration
     (a) Energize the aircraft electrical circuits
AMM 24-41-00-861-002.
     (b) Do the EIS start procedure (Upper ECAM DU and lower ECAM DU only)
AMM 31-60-00-860-001.
Subtask 24-50-00-710-066-A
B. Test
   (1) Do this test:
ACTION
RESULT
1.On the ELEC panel 35VU:
  • release the GEN 1 and GEN 2 pushbutton switches.
On the ELEC panel 35VU:
  • the OFF legends of the GEN 1 and GEN 2 pushbutton switches come on.
    On the upper ECAM display unit:
  • the ELEC AC BUS 1 FAULT and the ELEC AC ESS BUS FAULT warnings come into view.
4. Fault Isolation
Subtask 24-50-00-865-053-A
A. Table of the circuit breakers used in this procedure:
PANELDESIGNATIONFINLOCATION
** ON A/C ALL
122VUELEC/GEN1/OFF/BTC1 SPLY5XUT28
Subtask 24-50-00-810-058-A ** ON A/C NOT FOR ALL
B. If the test confirms the fault:
  • Do a check of the status of the ELEC/GEN1/OFF/BTC1 SPLY circuit breaker (5XU).
   (1) If the circuit breaker is closed:
     (a) If the fault continues:
     (b) If the fault continues:
       1 Remove the EPC auxiliary control-relay (5XG) and do a check for 28VDC at pin A/D3 on the base of the EPC auxiliary control-relay (5XG):
         a If there is 28VDC:
  • Replace the RELAY-EPC AUX CTL [5XG] .
         b If there is no 28VDC:
  • Repair the wiring between the ELEC/GEN1/OFF/BTC1 SPLY circuit breaker (5XU) and pin A/D3 of the EPC auxiliary control-relay (5XG) ASM 242202 and ASM 242302.
       2 Remove the GLC1 auxiliary control-relay (4XU1) and do a check for 28VDC at pin A/A3 on the base of the GLC1 auxiliary control-relay (4XU1):
         a If there is 28VDC:
  • Replace the RELAY-GLC 1 AUX CTL [4XU1] .
         b If there is no 28VDC:
  • Repair the wiring between pin A/D2 of the EPC auxiliary control-relay (5XG) and pin A/A3 of the GLC1 auxiliary control-relay (4XU1) ASM 242202 and ASM 242302.
       3 Do a check for 28VDC at pin B/8 of GLC1 (9XU1).
         a If there is no 28VDC:
         b If the fault continues:
  • Repair the wiring between pin A/A2 of the GLC1 auxiliary control-relay (4XU1) and pin B/24 of GLC1 (9XU1) ASM 242202.
       4 Do a check for 28VDC at pin B/3 of BTC1 (11XU1).
         a If there is no 28VDC:
  • Replace the RELAY-BUS TIE [30XU1] .
         b If the fault continues:
  • Do a check and repair the wiring between:
    . Pin B/6 of GLC1 (9XU1) and pins A/B2 and A/X1 of the BUS TIE relay (30XU1) ASM 242202,
    . Pin A/B3 of the BUS TIE relay (30XU1) and pin B/3 of BTC1 (11XU1) ASM 242202.
   (2) If the circuit breaker is open:
     (a) If the fault continues:
  • Replace the C/B-ELEC/GEN1/OFF/BTC1 SPLY [5XU] .
Subtask 24-50-00-810-058-B ** ON A/C NOT FOR ALL
B. If the test confirms the fault:
  • Do a check of the status of the ELEC/GEN1/OFF/BTC1 SPLY circuit breaker (5XU).
   (1) If the circuit breaker is closed:
     (a) If the fault continues:
     (b) If the fault continues:
       1 Remove the EPC auxiliary control-relay (5XG) and do a check for 28VDC at pin A/D3 on the base of the EPC auxiliary control-relay (5XG):
         a If there is 28VDC:
  • Replace the RELAY-EPC AUX CTL [5XG] .
         b If there is no 28VDC:
  • Repair the wiring between the ELEC/GEN1/OFF BTC1 SPLY circuit breaker (5XU) and pin A/D3 of the EPC auxiliary control-relay (5XG) ASM 242202 and ASM 242302.
       2 Remove the GLC1 auxiliary control-relay (4XU1) and do a check for 28VDC at pin A/A3 on the base of the GLC1 auxiliary control-relay (4XU1):
         a If there is 28VDC:
  • Replace the RELAY-GLC 1 AUX CTL [4XU1] .
         b If there is no 28VDC:
  • Repair the wiring between pin A/D2 of the EPC auxiliary control-relay (5XG) and pin A/A3 of the GLC1 auxiliary control-relay (4XU1) ASM 242202 and ASM 242302.
       3 Do a check for 28VDC at the pin B/22 of GLC1 (9XU1).
         a If there is no 28VDC:
         b If the fault continues:
  • Repair the wiring between pin A/A2 of GLC1 auxiliary control-relay (4XU1) and pin B/24 of GLC1 (9XU1) ASM 242202.
       4 Do a check for 28VDC at the pin B/3 of BTC1 (11XU1):
         a If there is no 28VDC:
  • Replace the RELAY-BUS TIE [30XU1] .
         b If the fault continues:
  • Do a check and repair the wiring ASM 242202 between:
    . Pin B/22 of GLC1 (9XU1) and pins A/B2 and A/X1 of the BUS TIE relay (30XU1)
    . Pin A/B3 of the BUS TIE relay (30XU1) and pin B/3 of BTC1 (11XU1).
   (2) If the circuit breaker is open:
     (a) If the fault continues:
  • Replace the C/B-ELEC/GEN1/OFF/BTC1 SPLY [5XU] .
Subtask 24-50-00-710-067-A
C. Do this test to make sure that the system operates correctly.
ACTION
RESULT
On the ECAM control panel:
  • push the ELEC key to get the ELEC page.
On the lower ECAM display unit:
  • the normal configuration comes into view.
5. Close-up
Subtask 24-50-00-860-065-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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