DOC AIRBUS | AMM A320FInstallation of the Power Supply Unit (PSU)
TASK 33-21-31-400-801-B
Installation of the Power Supply Unit (PSU)
1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Work Zones and Access Panels
C. Referenced Information
3. Job Set-up
Subtask 33-21-31-860-051-A ** ON A/C NOT FOR ALL
Subtask 33-21-31-210-051-A ** ON A/C NOT FOR ALL
Subtask 33-21-31-410-051-A ** ON A/C NOT FOR ALL
[Rev.10 from 2021]
2026.04.01 00:53:28 UTC
Installation of the Power Supply Unit (PSU)
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 | STEPLADDER 1.0 M (3.3 FT) |
| No specific | Torque wrench: range to between 0.46 and 0.4 m.daN (40.71 and 35.40 lbf.in )  |
| ZONE/ACCESS | ZONE DESCRIPTION |
|---|---|
| 240 | MID PASSENGER COMPARTMENT |
| FOR [572LG] (POWER SUPPLY UNIT) | |
| 241EC | |
| REFERENCE | DESIGNATION |
|---|---|
| TASK 20-28-00-912-802-A | Electrical Bonding - General Maintenance Procedure |
| TASK 20-28-00-912-803-A | Bonding Surface Preparation |
| 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) |
| TASK 25-23-41-000-001-A | Removal of the Ceiling Panels |
| TASK 33-21-00-710-001-A | Operational Test of the General Illumination |
| FOR [572LG] (POWER SUPPLY UNIT) | |
| TASK 25-23-41-400-001-A | Installation of the Ceiling Panels |
Power Supply Unit (PSU)Subtask 33-21-31-860-051-A ** ON A/C NOT FOR ALL
A. Aircraft Maintenance Configuration
(1) Make sure that the aircraft electrical circuits are energized
(Ref. AMM TASK 24-41-00-861-002).
(2) Make sure that the STEPLADDER 1.0 M (3.3 FT) is in the position below the related ceiling panel.
(3) Make sure that the related ceiling panel is removed (Ref. AMM TASK 25-23-41-000-001).
Subtask 33-21-31-865-053-A ** ON A/C NOT FOR ALL (1) Make sure that the aircraft electrical circuits are energized
(Ref. AMM TASK 24-41-00-861-002).
(2) Make sure that the STEPLADDER 1.0 M (3.3 FT) is in the position below the related ceiling panel.
(3) Make sure that the related ceiling panel is removed (Ref. AMM TASK 25-23-41-000-001).
B. Make sure that this(these) circuit breaker(s) is(are) open, safetied and tagged:
4. Procedure| PANEL | DESIGNATION | FIN | LOCATION |
|---|---|---|---|
| ** ON A/C NOT FOR ALL | |||
| 2000VU | LIGHT-HATRACK-STRIP | 312LG | J05 |
Subtask 33-21-31-210-051-A ** ON A/C NOT FOR ALL
A. Preparation for Installation
(1) Clean the component interfaces and the adjacent area.
(2) Do an inspection of the component interfaces and the adjacent area.
(3) Prepare the surface of the bonding point(s)
(Ref. AMM TASK 20-28-00-912-803).
Subtask 33-21-31-420-051-A ** ON A/C NOT FOR ALL (1) Clean the component interfaces and the adjacent area.
(2) Do an inspection of the component interfaces and the adjacent area.
(3) Prepare the surface of the bonding point(s)
(Ref. AMM TASK 20-28-00-912-803).
B. Installation of the PSU
(1) Put the PSU (1) in position on its support.
(2) Install the washers (2) and the screws (3).
(3) Tighten the screws (3).
(4) Install the bonding strap (6) and the nut (7).
(5) TORQUE the nut (7) to between 0.46 and 0.4 m.daN (40.71 and 35.40 lbf.in ).
(6) Give protection to the bonding point(s)
(Ref. AMM TASK 20-28-00-912-802).
(7) Remove the CAP-BLANKING from each electrical connector and receptacle.
Subtask 33-21-31-865-054-A ** ON A/C NOT FOR ALL (1) Put the PSU (1) in position on its support.
(2) Install the washers (2) and the screws (3).
(3) Tighten the screws (3).
(4) Install the bonding strap (6) and the nut (7).
(5) TORQUE the nut (7) to between 0.46 and 0.4 m.daN (40.71 and 35.40 lbf.in )
.(6) Give protection to the bonding point(s)
(Ref. AMM TASK 20-28-00-912-802).
(7) Remove the CAP-BLANKING from each electrical connector and receptacle.
CAUTION:
MAKE SURE THAT THE BONDING STRAP(S) IS(ARE) CONNECTED BEFORE YOU CONNECT THE ELECTRICAL CONNECTOR(S).
CAUTION:
MAKE SURE THAT THE ELECTRICAL CONNECTORS ARE CLEAN BEFORE YOU DISCONNECT OR CONNECT THEM. CONTAMINATION ON THE ELECTRICAL CONNECTORS CAN CAUSE DAMAGE TO EQUIPMENT.
CAUTION:
REFER TO THE MATCH MARKS MADE DURING THE REMOVAL WHEN YOU CONNECT THE ELECTRICAL WIRES.
INCORRECT CONNECTION OF THE WIRES WILL CAUSE DAMAGE TO EQUIPMENT.
(8) Connect the electrical connectors (4) and (5) to the PSU (1).C. Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s):
Subtask 33-21-31-710-051-A ** ON A/C NOT FOR ALL | PANEL | DESIGNATION | FIN | LOCATION |
|---|---|---|---|
| ** ON A/C NOT FOR ALL | |||
| 2000VU | LIGHT-HATRACK-STRIP | 312LG | J05 |
D. Operational Test
(1) Do the test of the SCENARIO lighting from the Flight Attendant Panel (FAP) (Ref. AMM TASK 33-21-00-710-001):
(a) Make sure that the underbin lights come on.
5. Close-up(1) Do the test of the SCENARIO lighting from the Flight Attendant Panel (FAP) (Ref. AMM TASK 33-21-00-710-001):
(a) Make sure that the underbin lights come on.
Subtask 33-21-31-410-051-A ** ON A/C NOT FOR ALL
A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Install the ceiling panel:
(a) FOR [572LG] (POWER SUPPLY UNIT)
Install 241EC (Ref. AMM TASK 25-23-41-400-001).
(3) Remove the STEPLADDER 1.0 M (3.3 FT).
Subtask 33-21-31-862-051-A ** ON A/C NOT FOR ALL (1) Make sure that the work area is clean and clear of tools and other items.
(2) Install the ceiling panel:
(a) FOR [572LG] (POWER SUPPLY UNIT)
Install 241EC (Ref. AMM TASK 25-23-41-400-001).
(3) Remove the STEPLADDER 1.0 M (3.3 FT).