W DOC AIRBUS | AMM A320F

Installation of the 115/26VAC Autotransformer

TASK 24-51-51-400-001-A
Installation of the 115/26VAC Autotransformer

WARNING: MAKE SURE THAT NO AC OR DC POWER IS CONNECTED TO THE AIRCRAFT ELECTRICAL CIRCUITS. THERE IS A RISK OF ELECTROCUTION IF THE AC OR DC POWER STAYS CONNECTED.
ZONE: 212
FIN: 15XN1
FIN: 15XN2
1. Reason for the Job
Self explanatory
2. Job Set-up Information
 A. Fixtures, Tools, Test and Support Equipment
REFERENCE
QTY
DESIGNATION
No specific
1
ACCESS PLATFORM 1M (3 FT)-ADJUSTABLE
No specific
AR
WARNING NOTICE(S)
 B. Work Zones and Access Panels
ZONE/ACCESS
ZONE DESCRIPTION
212
COCKPIT
121AL
 C. Referenced Information
REFERENCE
DESIGNATION
TASK 24-41-00-861-002-A
Energize the Aircraft Electrical Circuits from the External Power
TASK 24-41-00-861-002-A-01
Energize the Aircraft Electrical Circuits from the APU
TASK 24-41-00-861-002-A-02
Energize the Aircraft Electrical Circuits from Engine 1(2)
TASK 24-41-00-862-002-A
De-energize the Aircraft Electrical Circuits Supplied from the External Power
TASK 24-41-00-862-002-A-01
De-energize the Aircraft Electrical Circuits Supplied from the APU
TASK 24-41-00-862-002-A-02
De-energize the Aircraft Electrical Circuits Supplied from the Engine 1(2)
F Autotransformers
FOR [15XN1] (A/XFMR-115/26VAC, 1)
TASK 31-60-00-860-001-A
EIS Start Procedure
TASK 31-60-00-860-002-A
EIS Stop Procedure
3. Job Set-up
Subtask 24-51-51-860-051-A
A. Aircraft Maintenance Configuration
   (1) Make sure that the ACCESS PLATFORM 1M (3 FT)-ADJUSTABLE is in position at the access door 121AL.
   (2) Make sure that the access door 121AL is open.
   (3) Make sure that the external power connector is not connected to the aircraft receptacle.
   (4) Make sure that, on the access door 121AL, there is a WARNING NOTICE(S) to tell persons not to connect the external power connector.
   (5) In the cockpit, on the overhead ELEC panel 35VU, make sure that these pushbutton switches are released:
  • BAT 1, BAT 2,
  • APU GEN,
  • GEN 1, GEN 2,
  • EXT PWR.
   (6) Make sure that there is a WARNING NOTICE(S) in the cockpit to tell persons not to operate the pushbutton switches on these overhead panels:
  • 21VU (EMER ELEC PWR),
  • 35VU (ELEC).
   (7) In the cockpit, on the APU section of the overhead panel 25VU, make sure that a WARNING NOTICE(S) is in position to tell persons not to start the APU.
   (8) In the cockpit, make sure that the panel (6) which gives access to the panel 122VU is removed.
Subtask 24-51-51-865-051-A
B. Make sure that this(these) circuit breaker(s) is(are) open, safetied and tagged:
PANELDESIGNATIONFINLOCATION
** ON A/C ALL
FOR FIN: 15XN1 (A/XFMR115/26VAC, 1)
123VUBUS 1/131XP-A/SPLY5XN1AB12
FOR FIN: 15XN2 (A/XFMR115/26VAC, 2)
123VUBUS 2/231XP-A/SPLY5XN2AB01
4. Procedure
Subtask 24-51-51-420-050-A
A. Installation of the Autotransformer
   (1) Put the transformer (2) in position.
   (2) Install the washers (3) and the screws (4) and then tighten the screws.
   (3) Remove the blanking caps from the electrical connectors (1) and (5).
   (4) Make sure that all the electrical connections are clean and in the correct condition.
   (5) Connect the electrical connector (1).
Subtask 24-51-51-865-052-A
B. Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s):
PANELDESIGNATIONFINLOCATION
** ON A/C ALL
FOR FIN: 15XN1 (A/XFMR115/26VAC, 1)
123VUBUS 1/131XP-A/SPLY5XN1AB12
FOR FIN: 15XN2 (A/XFMR115/26VAC, 2)
123VUBUS 2/231XP-A/SPLY5XN2AB01
Subtask 24-51-51-710-050-A ** ON A/C NOT FOR ALL
C. Operational Test of the Autotransformer
   (1) Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
   (2) FOR [15XN1] (A/XFMR-115/26VAC, 1)
     (a) Do the EIS start procedure (Upper ECAM DU and lower ECAM DU only) (Ref. AMM TASK 31-60-00-860-001).
     (b) Get the HYD page.
     (c) Make sure that there is no cross on the HYDRAULIC quantity indications.
     (d) Do the EIS stop procedure (Ref. AMM TASK 31-60-00-860-002).
   (3) FOR [15XN2] (A/XFMR-115/26VAC, 2)
     (a) On the ADIRS CDU, put the OFF/NAV/ATT selector switch of the ADIRU 2 in NAV position.
     (b) Make sure that the FAULT legend on the ADR 2 pushbutton switch does not remain on.
Subtask 24-51-51-710-050-B ** ON A/C NOT FOR ALL
C. Operational Test of the Autotransformer
   (1) Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
   (2) FOR [15XN1] (A/XFMR-115/26VAC, 1)
     (a) Do the EIS start procedure (upper ECAM DU and lower ECAM DU only) (Ref. AMM TASK 31-60-00-860-001).
     (b) Get the HYD page.
     (c) Make sure that there is no cross on the HYDRAULIC quantity indications.
     (d) Do the EIS stop procedure (Ref. AMM TASK 31-60-00-860-002).
   (3) FOR [15XN2] (A/XFMR-115/26VAC, 2)
     (a) On the ADIRS MSU panel 41VU, set the OFF/NAV/ATT selector switch of the ADIRU 2 to the NAV position.
     (b) On the ADR 2 pushbutton switch, make sure that the FAULT legend does not stay on.
5. Close-up
Subtask 24-51-51-862-050-A
A. De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).
Subtask 24-51-51-410-050-A
B. Close Access
   (1) Make sure that the work area is clean and clear of tools and other items.
   (2) Remove the WARNING NOTICE(S).
   (3) Install the panel (6) which gives access to panel 122VU.
   (4) Close the access door 121AL.
   (5) Remove the access platform(s).
[Rev.10 from 2021] 2026.03.31 23:24:50 UTC
"Aviabrain" 2025