Removal of the DC Bus 1 Contactor Module

TASK 24-61-58-000-001-A
Removal of the DC Bus 1 Contactor Module

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.

FIN: 13PN ** ON A/C NOT FOR ALL

1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	ACCESS PLATFORM 1M (3 FT)-ADJUSTABLE
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
121AL

C. Referenced Information

REFERENCE	DESIGNATION
TASK 24-32-55-000-001-A	Removal of the TR 1 and TR 2 Contactors and the TR 2/AC Service Bus Normal Supply Contactor
TASK 24-35-55-000-001-A	Removal of the Contactor
TASK 25-11-41-000-001-A	Removal of the Third Occupant Seat
TASK 49-42-55-000-001-A	Removal of the Start Contactors
DC Bus 1 Contactor Module

3. Job Set-up
Subtask 24-61-58-010-050-A ** ON A/C NOT FOR ALL

A. Get Access
(1) Remove the Third Occupant seat (Ref. AMM TASK 25-11-41-000-001).
(2) In the cockpit, remove the front panel on the bottom right side of the rear panel 120VU.
(3) Put the ACCESS PLATFORM 1M (3 FT)-ADJUSTABLE in position at the access door 121AL.
(4) Open the access door 121AL.

Subtask 24-61-58-860-050-A ** ON A/C NOT FOR ALL

B. Safety Precautions
(1) Make sure that the external power connector is not connected to the aircraft external-power receptacle.
(2) Put a WARNING NOTICE(S) in position on the access door 121AL to tell persons not to connect the external power connector to the aircraft external-power receptacle.
(3) In the cockpit, on the ELEC panel 35VU, make sure that these pushbutton switches are released:

BAT 1, BAT 2
APU GEN
GEN 1, GEN 2
EXT PWR.

(4) In the cockpit, put a WARNING NOTICE(S) in position to tell persons not to operate the pushbutton switches on the overhead panel:

21VU (EMER ELEC PWR section)
25VU (APU section)
35VU (ELEC).

4. Procedure
Subtask 24-61-58-020-051-A ** ON A/C NOT FOR ALL

A. Removal of the Contactors Installed on the Contactor Module 13PN
(1) Remove the contactor 5PU1 (Ref. AMM TASK 24-32-55-000-001).
(2) Remove the contactor 1PC1 (Ref. AMM TASK 24-35-55-000-001).
(3) Remove the contactors 5KA and 10KA (Ref. AMM TASK 49-42-55-000-001).

Subtask 24-61-58-020-052-A ** ON A/C NOT FOR ALL

B. Removal of the Electrical Components

CAUTION: MAKE MATCH MARKS ON ALL THE ELECTRICAL WIRES BEFORE YOU DISCONNECT THEM. INCORRECT CONNECTION OF WIRES WILL CAUSE DAMAGE TO EQUIPMENT.

(1) Removal of the fuses (4).
(a) Remove the nuts (1).
(b) Remove and discard the locking washers (2) and disconnect the electrical cables (3).
(c) Remove the screws (17) and the washers (16).
(d) Remove the fuses (4).
(2) Removal of the fuse (10).
(a) Remove the nut (13).
(b) Remove and discard the locking washer (12) and disconnect the electrical cable (11).
(c) Remove the screw (15) and the washer (14).
(d) Remove the fuse (10) and the spacer (6).
(3) Removal of the busbar (7).
(a) Remove the screw (9) and the washer (8).
(b) Remove the busbar (7).
(4) Disconnection of the electrical cables.
(a) Remove the screws (20), the washers (19) and disconnect the electrical cables (18).
(b) Remove the screw (23), the washer (22) and disconnect the electrical cable (21).
(c) Remove the screw (27), the washer (28) and disconnect the electrical cables (29) and (30).

Subtask 24-61-58-020-050-A ** ON A/C NOT FOR ALL

C. Removal of the DC Bus 1 Contactor Module (13PN)
(1) Remove the protective plugs (24) from the screws (25).
(2) Remove the screws (25).
(3) Remove and discard the locking washers (26).
(4) Remove the contactor module (5).

[Rev.10 from 2021] 2026.04.01 05:49:40 UTC