Removal of the AC Current Transformer

TASK 24-23-17-000-001-A
Removal of the AC Current Transformer

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: 42XS

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	CAP - BLANKING
No specific	AR	TIE WRAP
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
121AL

C. Referenced Information

REFERENCE	DESIGNATION
TASK 25-11-41-000-001-A	Removal of the Third Occupant Seat
AC Current Transformer - Block Diagram ** ON A/C NOT FOR ALL
AC Current Transformer ** ON A/C NOT FOR ALL
AC Current Transformer - Block Diagram ** ON A/C NOT FOR ALL
AC Current Transformer ** ON A/C NOT FOR ALL

3. Job Set-up
Subtask 24-23-17-010-050-A

A. Get Access
(1) Remove the Third Occupant seat (Ref. AMM TASK 25-11-41-000-001).
(2) On the rear panel 120VU, open the panel which gives access to the AC power center 123VU.
(3) Put the ACCESS PLATFORM 1M (3 FT)-ADJUSTABLE in position at the access door 121AL.
(4) Open the access door 121AL.

Subtask 24-23-17-941-050-A

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

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

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

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

4. Procedure
Subtask 24-23-17-020-051-A ** ON A/C NOT FOR ALL

A. Removal of the AC Current Transformer

AC Current Transformer - Block Diagram ** ON A/C NOT FOR ALL

AC Current Transformer ** ON A/C NOT FOR ALL

(1) Remove the screws (12) and the washers (11) from the studs of the contactor (5).
(2) Disconnect the cables (10) from the studs of the contactor (5).

NOTE: You must identify (also with the indications on the current transformer) and disconnect only the cables which go through the current transformer.

(3) Remove the nuts (9) and the washers (8) from the studs of the contactor (5).
(4) Disconnect the cables (6) and (7) from the studs of the contactor (5).
(5) Disconnect the electrical connector (4) from the current transformer (1).
(6) Put CAP - BLANKING on the disconnected electrical connector (4) and electrical receptacle.
(7) Remove the screws (3) and the washers (2) from the current transformer (1).
(8) Remove the necessary TIE WRAP to move the current transformer (1) along the cables.
(9) Remove the current transformer (1).

Subtask 24-23-17-020-051-B ** ON A/C NOT FOR ALL

A. Removal of the AC Current Transformer

AC Current Transformer - Block Diagram ** ON A/C NOT FOR ALL

AC Current Transformer ** ON A/C NOT FOR ALL

(1) Remove the screws (12) and the washers (11) from the studs of the module 29XN.
(2) Disconnect the cables (10) from the studs of the module 29XN.

NOTE: You must identify (also with the indications on the current transformer) and disconnect only the cables which go through the current transformer.

(3) Remove the nuts (9) and the washers (8) from the studs of the module 29XN.
(4) Disconnect the cables (6) and (7) from the studs of the module 29XN.
(5) Disconnect the electrical connector (4) from the current transformer (1).
(6) Put CAP - BLANKING on the disconnected electrical connector (4) and electrical receptacle.
(7) Remove the screws (3) and the washers (2) from the current transformer (1).
(8) Remove and discard the necessary TIE WRAP to move the current transformer (1) along the cables.
(9) Remove the current transformer (1).

[Rev.10 from 2021] 2026.03.31 23:22:24 UTC