De-energize the Aircraft Electrical Circuits Supplied from the External Power

TASK 24-41-00-862-002-A
De-energize the Aircraft Electrical Circuits Supplied from the External Power

1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
121AL

B. Referenced Information

REFERENCE	DESIGNATION
External Power Receptacle - Location

3. Job Set-up
Subtask 24-41-00-869-067-A

A. Not Applicable

4. Procedure
Subtask 24-41-00-862-051-B

A. De-energize the aircraft electrical circuits from the external power
(1) On the ELEC panel 35VU, push and release the BAT1 and BAT2 pushbutton switches:

the OFF legends come on.

(2) On the panel 35VU, push the EXT PWR pushbutton switch:

the ON legend goes off,
the AVAIL legend comes on.

(3) The aircraft electrical circuits are correctly de-energized if:
(a) On the panel 35VU, these legends go off:

the FAULT legend of the GEN1 and GEN2 pushbutton switches,
the OFF legend of the BAT1 and BAT2 pushbutton switches,
the OFF legend of the GALY and CAB pushbutton switch.

(b) On the panel 108VU, the EXT PWR/NOT IN USE indicator light comes on.

5. Close-up
Subtask 24-41-00-080-051-A

A. Obey the instructions given with the ground power unit and stop the ground power unit.

On the panel 35VU, all the pushbutton switch legends are off.
On the panel 108VU, all the lights are off.

Subtask 24-41-00-020-050-A

B. Disconnect the connector

WARNING: DE-ENERGIZE THE ELECTRICAL POWER SUPPLY BEFORE YOU DISCONNECT THE CONNECTOR OF THE GROUND POWER UNIT. IF NOT DANGEROUS ARCING CAN OCCUR.

(1) Disconnect the connector of the ground power unit from the external power receptacle.

Subtask 24-41-00-080-050-A

C. Disconnect the snap hook from the fitting on the aircraft structure.
(1) Disconnect all the ground (earth) cables if necessary.

Subtask 24-41-00-410-051-A

D. Close Access
(1) Close the access door 121AL.

[Rev.10 from 2021] 2026.03.31 23:24:08 UTC