Operational Test of the IDG Disconnect and Reconnect (Reset) Function - Engine in Operation

TASK 24-21-00-720-042-A
Operational Test of the IDG Disconnect and Reconnect (Reset) Function - Engine in Operation

WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE PARTS AFTER THE ENGINE SHUTDOWN. USE APPLICABLE THERMAL GLOVES. THE ENGINE PARTS CAN STAY HOT FOR ONE HOUR AFTER SHUTDOWN AND CAN BURN YOU.

1. Reason for the Job
To do a check of the IDG disconnect system and reset system.
2. Job Set-up Information
A. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
FOR [1000EM1] (ENGINE-1)
438AR
FOR [1000EM2] (ENGINE-2)
448AR

B. 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)
TASK 31-60-00-860-001-A	EIS Start Procedure
TASK 31-60-00-860-002-A	EIS Stop Procedure
TASK 71-00-00-710-018-A	Discontinued Start, Restart and Shutdown Procedures
TASK 71-00-00-710-043-A	Normal Engine Automatic-Start Procedure
TASK 71-13-00-010-010-A	Opening of the Fan Cowls 437AL(447AL),438AR(448AR)
TASK 71-13-00-410-010-A	Closing of the Fan Cowls 437AL(447AL),438AR(448AR)

3. Job Set-up
Subtask 24-21-00-860-053-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
(2) Do the EIS start procedure (upper ECAM DU and lower ECAM DU only)
(Ref. AMM TASK 31-60-00-860-001).
(3) On the ECAM control panel, push the ELEC key to get the ELEC page.
(4) Start the engine 1(2) (Ref. AMM TASK 71-00-00-710-043).

Subtask 24-21-00-865-059-A ** ON A/C NOT FOR ALL

B. Make sure that this(these) circuit breaker(s) is(are) closed:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
122VU	ELEC/IDG2/DISC	2XT	T25
122VU	ELEC/IDG1/DISC	1XT	T24

4. Procedure

CAUTION: DO NOT PUSH THE IDG DISCONNECT PUSHBUTTON SWITCH IF THE ENGINE SPEED IS LESS THAN IDLE SPEED. IF YOU DO, YOU WILL CAUSE DAMAGE TO THE JAW TEETH, AT ENGINE START.

CAUTION: DO NOT PUSH THE IDG DISCONNECT PUSHBUTTON SWITCH FOR MORE THAN 3 SECONDS. THERE MUST BE AT LEAST 60 SECONDS BETWEEN TWO OPERATIONS OF THE SWITCH. THIS IS TO PREVENT DAMAGE TO THE DISCONNECT SOLENOID WHICH WILL BECOME TOO HOT.

Subtask 24-21-00-720-052-A ** ON A/C NOT FOR ALL

A. Operational Test of the IDG Disconnect Function - Engine in Operation

NOTE: This test is for the system 1. For the other system(s), use the indications between the parentheses.

ACTION	RESULT
1.With the engines at idle speed, on the ELEC control panel 35VU: lift the guard and push the IDG1(2) pushbutton switch.	On the ELEC control panel 35VU: the FAULT legend of the related GEN pushbutton switch comes on
	On the lower ECAM display unit, on the ELEC page: the load, voltage and frequency parameters of the related generator are zero, the amber DISC indication comes into view under the indication IDG, the external power energizes the aircraft electrical circuits.
2.On the ELEC control panel 35VU: Release the GEN1(2) pushbutton switch.	On the ELEC control panel 35VU: the FAULT legend of the related GEN pushbutton switch goes off,
3.On the ELEC control panel 35VU: Push the guard of the IDG 1(2) pushbutton switch back in position.

Subtask 24-21-00-710-055-A ** ON A/C NOT FOR ALL

B. Reset of the system
(1) Stop the engine (Ref. AMM TASK 71-00-00-710-018).

Subtask 24-21-00-010-064-A ** ON A/C NOT FOR ALL

C. Open the right fan-cowl door (Ref. AMM TASK 71-13-00-010-010):
(1) FOR [1000EM1] (ENGINE-1)
438AR
(2) FOR [1000EM2] (ENGINE-2)
448AR

Subtask 24-21-00-720-053-A ** ON A/C NOT FOR ALL

D. Reset of the IDG 1(2) Disconnect System

CAUTION: MAKE SURE THE ENGINE IS STOPPED BEFORE YOU PULL THE DISCONNECT RESET RING. IF NOT YOU WILL CAUSE DAMAGE TO THE JAW TEETH.

CAUTION: MAKE SURE THAT THERE IS CORRECT RESET OF THE IDG DISCONNECT MECHANISM. IF THE RESET IS NOT CORRECT, YOU MUST REMOVE AND REPLACE THE IDG BEFORE THE NEXT FLIGHT.

(1) Slowly, pull out the disconnect reset ring to the full limit of travel. Monitor the hand force that is necessary: this force must not be too high. The disconnect mechanism must move freely without hard points.

NOTE: The disconnect solenoid will make a click that you can feel in the disconnect reset ring when the reset ring comes near the full travel limit.

(2) Let the disconnect reset ring go slowly back to the initial position.
(3) Again, slowly pull out the disconnect reset ring to the full limit of travel.
Monitor the hand force that is necessary. If the reset of the disconnect mechanism is correct, This force will be much less than in step (1). Also there will be no indication of the reset of the disconnect mechanism.
(4) On the ELEC control panel 35VU, push the GEN 1(2) pushbutton switch (the FAULT legend comes on).
(5) When you do the first engine start-up, make sure that the related electrical generation system operates correctly

NOTE: If the IDG was disconnected , the next engine start will clear the DISC indication on the ELEC page on the lower ECAM DU.

NOTE: If you start the engine after the test, you must do a GCU reset. To do this, release then push the related GEN pushbutton switch.

5. Close-up
Subtask 24-21-00-410-064-A ** ON A/C NOT FOR ALL

A. Close Access
(1) Close the right fan-cowl door (Ref. AMM TASK 71-13-00-410-010):
(a) FOR [1000EM1] (ENGINE-1)
438AR
(b) FOR [1000EM2] (ENGINE-2)
448AR

Subtask 24-21-00-860-054-A ** ON A/C NOT FOR ALL

B. Put the aircraft back to its initial configuration.
(1) Do the EIS stop procedure
(Ref. AMM TASK 31-60-00-860-002).
(2) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).

[Rev.10 from 2021] 2026.03.31 23:20:08 UTC