W DOC AIRBUS | TSM A320F

Failure of the GEN 2 Feeders or the Current Transformer Assembly


TASK 24-20-00-810-925-A
Failure of the GEN 2 Feeders or the Current Transformer Assembly


1. Possible Causes
  • feeders
  • CT-AC, 2 [41XU2]
  • wiring
  • GCU-2 [1XU2]
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
ASM 242201
AMM 24-22-17-000-002
Removal of the AC Current Transformers
AMM 24-22-17-400-002
Installation of the AC Current Transformers
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 24-41-00-740-002
Operational Check of the GAPCU via the CFDS
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
AMM 31-60-00-860-002
EIS Stop Procedure
AMM 71-00-00-710-003
Engine Automatic Start
AMM 71-00-00-710-028
Engine Shutdown
AMM 71-00-00-860-814
Shutdown of the Engine
AMM 71-00-00-860-823
Start the Engine (Normal Automatic Start)
3. Fault Confirmation
Subtask 24-20-00-869-079-A ** ON A/C NOT FOR ALL
A. Test
Not applicable.
NOTE: As the GEN 2 was set to OFF because of a true failure, the fault confirmation is not necessary.
4. Fault Isolation
Subtask 24-20-00-810-146-A ** ON A/C NOT FOR ALL
A. If the fault symptom is identified by the CFDS message WRG: GEN2 FEEDER/ CTA (41XU2) and the upper ECAM-DU warning GEN 2 FAULT:
  • do a check of the feeders ASM 242201 for an open circuit between:
    . terminal block T1 of the IDG 2 and terminal 1 of the 1998VT
    . terminal block T2 of the IDG 2 and terminal 2 of the 1998VT
    . terminal block T3 of the IDG 2 and terminal 3 of the 1998VT.
   (1) If the feeders are not correct:
  • repair or replace the feeders as necessary.
   (2) If the feeders are correct:
  • do an electrical resistance test of the Current Transformer Assembly (CTA) (41XU2) between:
    . pins A and G (6.725 ohms plus or minus 2.075 ohms)
    . pins B and G (6.725 ohms plus or minus 2.075 ohms)
    . pins C and G (6.725 ohms plus or minus 2.075 ohms).
     (a) If the resistance values are out of the specified limits:
     (b) If the resistance values are in the specified limits:
  • do a check of the wiring ASM 242201 for a short circuit between:
    . pins A, B and C of the CTA and pin A/15B of the GCU 2
    . pin G of the CTA and pin A/14B of the GCU 2.
       1 If the wiring is not correct:
  • repair or replace as necessary.
       2 If the wiring is correct:
Subtask 24-20-00-710-124-C ** ON A/C NOT FOR ALL
B. Do this operational test to make sure that the system operates correctly.
   (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.
   (2) In the cockpit, on the ELEC panel 35VU:
  • Push, release and push again the GEN 2 pushbutton switch (3XU2).
   (3) Do the BITE test of the GAPCU AMM 24-41-00-740-002.
   (4) Start engine 2 AMM 71-00-00-860-823.
   (5) Do this test:
ACTION
RESULT
On the ECAM control panel:
  • Push the ELEC key to get the ELEC page.
On the lower ECAM DU:
  • The correct electrical parameters of GEN 2 are shown and GEN 2 supplies the AC2 busbar.
Subtask 24-20-00-710-124-F ** ON A/C NOT FOR ALL
B. Do this operational test to make sure that the system operates correctly.
   (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.
   (2) On the ELEC panel 35VU:
  • push, release and push again the GEN 2 pushbutton switch (3XU2).
   (3) Do the operational test of the GAPCU AMM 24-41-00-740-002.
   (4) Start the engine 2 AMM 71-00-00-710-003.
   (5) Do this test:
ACTION
RESULT
On the ECAM control panel:
  • get the ELEC page.
On the lower ECAM DU:
  • the correct electrical parameters of the GEN 2 are shown and the AC2 busbar is supplied by the GEN 2.
5. Close-up
Subtask 24-20-00-860-149-C ** ON A/C NOT FOR ALL
A. Put the aircraft back to its initial configuration.
   (1) Stop engine 2 AMM 71-00-00-860-814.
   (2) Do the EIS stop procedure
AMM 31-60-00-860-002.
   (3) On the ECAM control panel, set the UPPER DISPLAY and LOWER DISPLAY potentiometers to OFF.
   (4) De-energize the aircraft electrical circuits
AMM 24-41-00-862-002.
Subtask 24-20-00-860-149-F ** ON A/C NOT FOR ALL
A. Put the aircraft back to its initial configuration.
   (1) Stop the engine 2 AMM 71-00-00-710-028.
   (2) Do the EIS stop procedure
AMM 31-60-00-860-002.
   (3) On the ECAM control panel, set the UPPER DISPLAY and LOWER DISPLAY potentiometers to OFF.
   (4) De-energize the aircraft electrical circuits
AMM 24-41-00-862-002.
[Rev.8 from Aug 2018] 2026.04.04 04:26:24 UTC