DOC AIRBUS | AMM A320FENGINE LP FUEL SHUT OFF - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL
1. General
The engine LP fuel shut-off system controls the LP fuel-valves. Each LP fuel-valve isolates its engine from the fuel supply at the front spar.
The related ENG MASTER switch (Ref. AMM D/O 76-12-00-00) controls the operation of the LP fuel-valve. But if the related engine FIRE PUSH switch (Ref. AMM D/O 26-12-00-00) is operated the LP fuel-valve closes.
The Engine/Warning Display (EWD) (Ref. AMM D/O 31-66-00-00) and the System Display (SD) (which together make the ECAM) give engine LP fuel shut-off information to the crew. If specified failures occur:
** ON A/C NOT FOR ALL The engine LP fuel shut-off system controls the LP fuel-valves. Each LP fuel-valve isolates its engine from the fuel supply at the front spar.
The related ENG MASTER switch (Ref. AMM D/O 76-12-00-00) controls the operation of the LP fuel-valve. But if the related engine FIRE PUSH switch (Ref. AMM D/O 26-12-00-00) is operated the LP fuel-valve closes.
NOTE: If the LP fuel-valve of one engine is closed, all the fuel in the aircraft is still available to the other engine.
The Engine/Warning Display (EWD) (Ref. AMM D/O 31-66-00-00) and the System Display (SD) (which together make the ECAM) give engine LP fuel shut-off information to the crew. If specified failures occur:
- a warning is given on the EWD
- the FUEL page shows on the SD.
2. Component Location
** ON A/C NOT FOR ALL | FIN | FUNCTIONAL DESIGNATION | PANEL | ZONE | ACCESS DOOR | ATA REF |
|---|---|---|---|---|---|
| ** ON A/C NOT FOR ALL | |||||
| 12QM | VALVE-LP FUEL, ENG 1 | 521AZ | 520 | 28-24-41 | |
| ** ON A/C NOT FOR ALL | |||||
| 12QM | VALVE-LP FUEL, ENG 1 | 520 | 28-24-41 | ||
| ** ON A/C NOT FOR ALL | |||||
| 13QM | VALVE-LP FUEL, ENG 2 | 621AZ | 620 | 28-24-41 | |
| ** ON A/C NOT FOR ALL | |||||
| 13QM | VALVE-LP FUEL, ENG 2 | 620 | 28-24-41 | ||
| ** ON A/C ALL | |||||
| 9QG | ACTUATOR-LP FUEL VALVE, ENG 1 | 521AZ | 520 | 28-24-51 | |
| 10QG | ACTUATOR-LP FUEL VALVE, ENG 2 | 621AZ | 620 | 28-24-51 | |
| 80QM | V BAND CLAMP-LP VALVE ACTR, ENG 1 | 521AZ | 520 | 28-10-00 | |
| 81QM | V BAND CLAMP-LP VALVE ACTR, ENG 2 | 621AZ | 620 | 28-10-00 | |
3. System Description
The LP fuel shut-off system has two independent electrical control circuits for each LP fuel-valve. They connect through a control relay to these related switches:
The LP fuel-valve 12QM(13QM) is in the fuel supply line to its related engine. The LP fuel-valve is usually open and in this configuration lets fuel through to its related engine. When one of the LP fuel-valves is closed, the fuel is isolated from that LP fuel valve's related engine.
The LP fuel-valve is installed between the engine pylon and the front face of the wing front spar (between RIB8 and RIB9).
Each LP fuel-valve has an actuator 9QG(10QG). The interface between the actuator and the LP fuel-valve is a valve spindle. When the actuator is energized, it moves the LP fuel-valve to the open or closed position. A V-band clamp 80QM(81QM) attaches the actuator to the LP fuel-valve.
Each actuator has two motors, which get their power supply from different sources:
If damage occurs to the electrical circuit, it is necessary to make sure that the valve can still operate. Thus the electrical supply to each motor goes through a different routing. The routing for motor 1 is along the front spar. The routing for motor 2 is along the rear spar and then forward through the flap track fairing at RIB6.
The actuators send position data to the System Data-Acquisition Concentrators (SDAC1 and SDAC2) (Ref. AMM D/O 31-54-00-00). The SDACs process the data and send it to the ECAM which shows the information on the FUEL page.
** ON A/C NOT FOR ALL The LP fuel shut-off system has two independent electrical control circuits for each LP fuel-valve. They connect through a control relay to these related switches:
- the ENG MASTER switch (Ref. AMM D/O 76-12-00-00)
- the FIRE PUSH switch (Ref. AMM D/O 26-12-00-00).
The LP fuel-valve 12QM(13QM) is in the fuel supply line to its related engine. The LP fuel-valve is usually open and in this configuration lets fuel through to its related engine. When one of the LP fuel-valves is closed, the fuel is isolated from that LP fuel valve's related engine.
The LP fuel-valve is installed between the engine pylon and the front face of the wing front spar (between RIB8 and RIB9).
Each LP fuel-valve has an actuator 9QG(10QG). The interface between the actuator and the LP fuel-valve is a valve spindle. When the actuator is energized, it moves the LP fuel-valve to the open or closed position. A V-band clamp 80QM(81QM) attaches the actuator to the LP fuel-valve.
Each actuator has two motors, which get their power supply from different sources:
- the 28VDC ESS BUS supplies the motor 1
- the 28VDC BUS 2 supplies the motor 2.
If damage occurs to the electrical circuit, it is necessary to make sure that the valve can still operate. Thus the electrical supply to each motor goes through a different routing. The routing for motor 1 is along the front spar. The routing for motor 2 is along the rear spar and then forward through the flap track fairing at RIB6.
The actuators send position data to the System Data-Acquisition Concentrators (SDAC1 and SDAC2) (Ref. AMM D/O 31-54-00-00). The SDACs process the data and send it to the ECAM which shows the information on the FUEL page.
** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL
6. Component Description
A. LP Fuel Valve FIN: 12-QM FIN: 13-QM
The LP fuel-valve has:
The valve body contains the ball-valve which has a bore of 38.1 mm (1.5 in). The ball valve is connected to the LP valve actuator by the valve spindle. A location slot makes sure that the valve spindle engages correctly with the actuator. The thermal relief valve is installed in the ball valve. When the LP valve is closed, the thermal relief valve operates at 0.83 bar (12 psi) to 1.52 bar (22 psi) to release downstream fuel-pressure (caused through thermal expansion) back through the valve. The LP valve is installed on the front-face of the wing front spar by the mounting flange.
The LP fuel-valve has:
- a valve body
- a ball valve with a thermal relief valve
- a valve spindle
- a mounting flange.
The valve body contains the ball-valve which has a bore of 38.1 mm (1.5 in). The ball valve is connected to the LP valve actuator by the valve spindle. A location slot makes sure that the valve spindle engages correctly with the actuator. The thermal relief valve is installed in the ball valve. When the LP valve is closed, the thermal relief valve operates at 0.83 bar (12 psi) to 1.52 bar (22 psi) to release downstream fuel-pressure (caused through thermal expansion) back through the valve. The LP valve is installed on the front-face of the wing front spar by the mounting flange.
B. LP Fuel Valve Actuator 9QG(10QG)
The LP fuel-valve actuator has two electrical motors which drive the same differential-gear to turn the ball valve through 90 deg. The limit switches in the actuator control this 90 deg. movement and set the electrical circuit for the next operation. One of the two motors can open or close the valve if the other motor does not operate.
The actuator drive shaft has a see/feel indicator where it goes through the actuator body. The see/feel indicator gives an indication of the valve position without removal of the LP fuel-valve.
The LP fuel-valve actuator has two electrical motors which drive the same differential-gear to turn the ball valve through 90 deg. The limit switches in the actuator control this 90 deg. movement and set the electrical circuit for the next operation. One of the two motors can open or close the valve if the other motor does not operate.
The actuator drive shaft has a see/feel indicator where it goes through the actuator body. The see/feel indicator gives an indication of the valve position without removal of the LP fuel-valve.
7. Operation/Control and Indicating
The engine LP fuel shut-off system is controlled manually. For the system to operate it is necessary to:
There is one LP fuel-valve for each engine, and each engine has an equivalent circuit. Thus as each LP fuel-valve circuit is the same, only the operation of the No. 1 engine circuit is given here.
The engine LP fuel shut-off system is controlled manually. For the system to operate it is necessary to:
- energize the 28VDC ESS BUS 1 (401PP)
- energize the 28VDC BUS 2 (206PP)
- close the circuit breakers 1QG, 2QG, 3QG and 4QG.
There is one LP fuel-valve for each engine, and each engine has an equivalent circuit. Thus as each LP fuel-valve circuit is the same, only the operation of the No. 1 engine circuit is given here.
A. Operation
When the No. 1 ENG MASTER switch (Ref. AMM D/O 76-12-00-00) is set to ON, it disconnects a 28VDC supply from the relay 11QG (HP FUEL SOV SOL P/BSW). The relay 11QG de-energizes and connects a 28VDC supply (through the ENG 1 FIRE PUSH switch (Ref. AMM D/O 26-12-00-00)) to the 'open' side of the LP fuel-valve actuator. The actuator then opens the LP fuel-valve.
When the No. 1 ENG MASTER switch is set to OFF, it connects a 28VDC supply to the relay 11QG. The relay energizes and connects a 28VDC supply (through the ENG 1 FIRE PUSH switch) to the 'close' side LP fuel-valve actuator. The actuator then closes the LP fuel-valve.
If the ENG 1 FIRE PUSH switch is operated:
When the No. 1 ENG MASTER switch (Ref. AMM D/O 76-12-00-00) is set to ON, it disconnects a 28VDC supply from the relay 11QG (HP FUEL SOV SOL P/BSW). The relay 11QG de-energizes and connects a 28VDC supply (through the ENG 1 FIRE PUSH switch (Ref. AMM D/O 26-12-00-00)) to the 'open' side of the LP fuel-valve actuator. The actuator then opens the LP fuel-valve.
When the No. 1 ENG MASTER switch is set to OFF, it connects a 28VDC supply to the relay 11QG. The relay energizes and connects a 28VDC supply (through the ENG 1 FIRE PUSH switch) to the 'close' side LP fuel-valve actuator. The actuator then closes the LP fuel-valve.
If the ENG 1 FIRE PUSH switch is operated:
- it disconnects the 28VDC supply to the 'open' side of the LP fuel-valve actuator
- it connects a 28VDC supply to the 'close' side of the LP fuel valve actuator - the LP fuel-valve moves to the closed position.
NOTE: The LP fuel-valve opens(closes) when the ENG MASTER switch is set to ON(OFF). But the operation of the engine FIRE PUSH switch always overrides an ON selection and closes the valve. A guard on the FIRE PUSH switch prevents an accidental operation.
B. Cockpit Indications
SD (FUEL Page) - LP Valve Indications ** ON A/C NOT FOR ALL
SD (FUEL Page) - LP Valve Indications ** ON A/C NOT FOR ALL
SD (Fuel Page) - LP Valve Indications ** ON A/C NOT FOR ALL
SD (Fuel Page) - LP Valve Indications ** ON A/C NOT FOR ALL
SD (FUEL Page) - LP Valve Indications ** ON A/C NOT FOR ALL
SD (Fuel Page) - LP Valve Indications ** ON A/C NOT FOR ALL
SD (Fuel Page) - LP Valve Indications ** ON A/C NOT FOR ALL
SD (FUEL Page) - LP Valve Indications ** ON A/C NOT FOR ALL
SD (FUEL Page) - LP Valve Indications ** ON A/C NOT FOR ALL SD (FUEL Page) - LP Valve Indications ** ON A/C NOT FOR ALL SD (Fuel Page) - LP Valve Indications ** ON A/C NOT FOR ALL SD (Fuel Page) - LP Valve Indications ** ON A/C NOT FOR ALL SD (FUEL Page) - LP Valve Indications ** ON A/C NOT FOR ALL SD (Fuel Page) - LP Valve Indications ** ON A/C NOT FOR ALL SD (Fuel Page) - LP Valve Indications ** ON A/C NOT FOR ALL SD (FUEL Page) - LP Valve Indications ** ON A/C NOT FOR ALL (1) SD (FUEL Page) Indications
When necessary, the crew can make a selection on the ECAM control-panel to look at the FUEL page.
When necessary, the crew can make a selection on the ECAM control-panel to look at the FUEL page.
(2) EWD Indication
If certain failures occur in the engine LP fuel shut-off system they cause:
If certain failures occur in the engine LP fuel shut-off system they cause:
- the Flight Warning System (FWS) (Ref. AMM D/O 31-51-00-00) to give an aural and visual warning
- the ECAM to show a failure message on the EWD, and the FUEL page to show on the SD.
- ENG 1(2) LP VALVE OPEN
8. BITE Test
Not applicable
Not applicable