DOC AIRBUS | AMM A320FCONTROL AND INDICATING - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL
1. General
The crew oxygen system has control and indicating functions.
In the cockpit, on the OXYGEN section of overhead control and indicating panel 21VU, the CREW SUPPLY pushbutton switch (2HT) controls the opening of the Low Pressure (LP) oxygen-supply solenoid valve (3HT).
The status and the warnings related to the system pressure are shown on:
In the cockpit, on the OXYGEN section of overhead control and indicating panel 21VU, the CREW SUPPLY pushbutton switch (2HT) controls the opening of the two Low Pressure (LP) oxygen-supply solenoid valves (3HT1 and 3HT2) at the same time.
The status and the warnings related to the system pressure are shown on:
Control and Indicating-Schematic ** ON A/C NOT FOR ALL
Control and Indicating-Schematic ** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL The crew oxygen system has control and indicating functions.
In the cockpit, on the OXYGEN section of overhead control and indicating panel 21VU, the CREW SUPPLY pushbutton switch (2HT) controls the opening of the Low Pressure (LP) oxygen-supply solenoid valve (3HT).
The status and the warnings related to the system pressure are shown on:
- The ECAM Display Units (DUs) (the DOOR/OXY page on the lower ECAM DU and warning/resolution messages on the Engine/Warning Display (EWD))
- A direct-reading pressure gage installed on the crew oxygen-storage cylinder gives an indication of the cylinder high-pressure level
- An overboard discharge indicator.
In the cockpit, on the OXYGEN section of overhead control and indicating panel 21VU, the CREW SUPPLY pushbutton switch (2HT) controls the opening of the two Low Pressure (LP) oxygen-supply solenoid valves (3HT1 and 3HT2) at the same time.
The status and the warnings related to the system pressure are shown on:
- The ECAM Display Units (DUs) (the DOOR/OXY page on the lower ECAM DU and warning/resolution messages on the Engine/Warning Display (EWD))
- A direct-reading pressure gage installed on each crew oxygen-storage cylinder
- An overboard discharge indicator.
Control and Indicating-Schematic ** ON A/C NOT FOR ALL Control and Indicating-Schematic ** ON A/C NOT FOR ALL 2. Component Location
** ON A/C NOT FOR ALL | FIN | FUNCTIONAL DESIGNATION | PANEL | ZONE | ACCESS DOOR | ATA REF |
|---|---|---|---|---|---|
| ** ON A/C NOT FOR ALL | |||||
| 5755HM | TEST PORT-OXY SYS | 125 | 35-13-41 | ||
| 5756HM | IND-OXY OVERBOARD DISCH | 125 | 35-13-22 | ||
| ** ON A/C NOT FOR ALL | |||||
| 5755HM1 | PORT.ASSY TEST | 125 | 35-13-41 | ||
| 5755HM2 | PORT.ASSY TEST | 126 | 35-13-41 | ||
| 5756HM1 | IND.DISCHARGE | 125 | 35-13-22 | ||
| 5756HM2 | IND.DISCHARGE | 126 | 35-13-22 | ||
| ** ON A/C NOT FOR ALL | |||||
| 4WV | PRESS SW-OXYGEN LO PR | 125 | 35-13-14 | ||
| ** ON A/C NOT FOR ALL | |||||
| 4WV1 | PRESSURE SWITCH | 125 | 35-13-14 | ||
| 4WV2 | PRESSURE SWITCH | 125 | 35-13-14 | ||
| ** ON A/C ALL | |||||
| 2HT | P/BSW-OXYGEN/CREW SUPPLY | 21VU | 211 | 35-13-00 | |
| ** ON A/C NOT FOR ALL | |||||
| 3HT | SOL VALVE-LP OXY SPLY | 126 | 35-13-51 | ||
| ** ON A/C NOT FOR ALL | |||||
| 3HT | SOL VALVE-LP OXY SPLY | 125 | 35-13-51 | ||
| ** ON A/C NOT FOR ALL | |||||
| 3HT1 | LP SOLENOID SUPPLY VALVE | 125 | 35-13-51 | ||
| 3HT2 | LP SOLENOID SUPPLY VALVE | 126 | 35-13-51 | ||
| ** ON A/C ALL | |||||
| 4HT | XMTR/PRESS REG-OXY | 125 | 35-13-15 | ||
| ** ON A/C NOT FOR ALL | |||||
| 4HT2 | PRESS.TRANSM.REGULATO | 126 | 35-13-15 | ||
| ** ON A/C NOT FOR ALL | |||||
| 5HT | IND-OXY FILLING | 125 | 35-13-21 | ||
| ** ON A/C NOT FOR ALL | |||||
| 5HT1 | IND OXY FILLING | 125 | 35-13-21 | ||
| 5HT2 | IND OXY FILLING | 125 | 35-13-21 | ||
3. System Description
A. Filling Indicator
The filling indicator (5HT) is installed near the replenishing connector. The filling indicator reads the pressure inner side of the cylinder while filling:
From 0 bar (0.0 psi) to 5.86 bar (85.0 psi): RED
From 5.86 bar (85.0 psi) to 137.9 bar (2000 psi): GREEN.
The filling indicators (5HT1 and 5HT2) are installed near the replenishing connectors. The filling indicator reads the pressure inner side of the cylinder while filling:
From 0 bar (0 psi) to 5.86 bar (85 psi): RED
From 5.86 bar (85 psi) to 137.9 bar (2000 psi): GREEN.
The filling indicator (5HT) is installed near the replenishing connector. The filling indicator reads the pressure inner side of the cylinder while filling:
From 0 bar (0.0 psi) to 5.86 bar (85.0 psi): RED
From 5.86 bar (85.0 psi) to 137.9 bar (2000 psi): GREEN.
The filling indicators (5HT1 and 5HT2) are installed near the replenishing connectors. The filling indicator reads the pressure inner side of the cylinder while filling:
From 0 bar (0 psi) to 5.86 bar (85 psi): RED
From 5.86 bar (85 psi) to 137.9 bar (2000 psi): GREEN.
4. Operation/Control and Indicating
A. Cockpit Indications
Crew Oxygen System - ECAM Data ** ON A/C NOT FOR ALL
Crew Oxygen System - ECAM Data ** ON A/C NOT FOR ALL
Crew Oxygen System - ECAM Data ** ON A/C NOT FOR ALL
Crew Oxygen System - ECAM Data ** ON A/C NOT FOR ALL Crew Oxygen System - ECAM Data ** ON A/C NOT FOR ALL Crew Oxygen System - ECAM Data ** ON A/C NOT FOR ALL B. Controls
(1) CREW SUPPLY Pushbutton Switch (2HT)
In the cockpit, on the OXYGEN section of overhead control and indicating panel 21VU, the CREW SUPPLY pushbutton switch sends a 28VDC control signal to the LP oxygen-supply solenoid valve (3HT).
Thus, the LP oxygen-supply solenoid valve opens and the LP oxygen flows into the distribution circuit.
ESS BUS busbar 801PP supplies 28VDC to the CREW SUPPLY pushbutton switch through circuit breaker 1HT.
A switch sends a signal for the position of the LP oxygen-supply solenoid valve to the System Data Acquisition Concentrator (SDAC) for monitoring and display.
In the cockpit, on the OXYGEN section of overhead control and indicating panel 21VU, the CREW SUPPLY pushbutton switch sends a 28VDC control signal to the LP oxygen-supply solenoid valve (3HT).
Thus, the LP oxygen-supply solenoid valve opens and the LP oxygen flows into the distribution circuit.
ESS BUS busbar 801PP supplies 28VDC to the CREW SUPPLY pushbutton switch through circuit breaker 1HT.
A switch sends a signal for the position of the LP oxygen-supply solenoid valve to the System Data Acquisition Concentrator (SDAC) for monitoring and display.
(2) CREW SUPPLY Pushbutton Switch (2HT)
In the cockpit, on the OXYGEN section of overhead control and indicating panel 21VU, the CREW SUPPLY pushbutton switch sends a 28VDC control signal to the LP oxygen-supply solenoid valves (3HT1 and 3HT2) at the same time.
Thus, the LP oxygen-supply solenoid valves open and the LP oxygen flows into the two distribution circuits.
ESS BUS busbar 801PP supplies 28VDC to the CREW SUPPLY pushbutton switch through circuit breaker 1HT.
A switch sends a signal for the position of the LP oxygen-supply solenoid valves to the two System Data Acquisition Concentrators (SDACs) for monitoring and display.
In the cockpit, on the OXYGEN section of overhead control and indicating panel 21VU, the CREW SUPPLY pushbutton switch sends a 28VDC control signal to the LP oxygen-supply solenoid valves (3HT1 and 3HT2) at the same time.
Thus, the LP oxygen-supply solenoid valves open and the LP oxygen flows into the two distribution circuits.
ESS BUS busbar 801PP supplies 28VDC to the CREW SUPPLY pushbutton switch through circuit breaker 1HT.
A switch sends a signal for the position of the LP oxygen-supply solenoid valves to the two System Data Acquisition Concentrators (SDACs) for monitoring and display.
(3) System Data Acquisition Concentrator (SDAC)
(Ref. AMM D/O 31-54-00-00)
Each SDAC receives the High Pressure (HP) oxygen values from the HP chambers of the oxygen pressure regulator/transmitter (4HT).
If the LP switch (4WV) is activated, it sends a signal to the SDAC.
Thus, each SDAC also receives the LP oxygen status.
Then, each SDAC transmits these HP oxygen values (and the LP oxygen status if the LP switch is activated) to the DOOR/OXY page of the lower ECAM DU.
(Ref. AMM D/O 31-54-00-00)
Each SDAC receives the High Pressure (HP) oxygen values from the HP chambers of the oxygen pressure regulator/transmitter (4HT).
If the LP switch (4WV) is activated, it sends a signal to the SDAC.
Thus, each SDAC also receives the LP oxygen status.
Then, each SDAC transmits these HP oxygen values (and the LP oxygen status if the LP switch is activated) to the DOOR/OXY page of the lower ECAM DU.
(4) System Data Acquisition Concentrator (SDAC)
(Ref. AMM D/O 31-54-00-00)
Each SDAC receives the High Pressure (HP) oxygen values from the HP chambers of the oxygen pressure regulator/transmitters (4HT and 4HT2).
If an LP switch (4WV1 or 4WV2) is activated, it sends a signal to the SDAC.
Thus, each SDAC also receives the LP oxygen status.
Then, each SDAC transmits these HP oxygen values (and the LP oxygen status if an LP switch is activated) to the DOOR/OXY page of the lower ECAM DU.
(Ref. AMM D/O 31-54-00-00)
Each SDAC receives the High Pressure (HP) oxygen values from the HP chambers of the oxygen pressure regulator/transmitters (4HT and 4HT2).
If an LP switch (4WV1 or 4WV2) is activated, it sends a signal to the SDAC.
Thus, each SDAC also receives the LP oxygen status.
Then, each SDAC transmits these HP oxygen values (and the LP oxygen status if an LP switch is activated) to the DOOR/OXY page of the lower ECAM DU.
(5) System Test
The test port (5755HM) is used for the pressure and leak tests on the ground.
The test port is connected through tubes to the LP distribution manifold (5753HM).
The test port (5755HM) is used for the pressure and leak tests on the ground.
The test port is connected through tubes to the LP distribution manifold (5753HM).
(6) System Test
Two test ports (5755HM1 and 5755HM2) are used for the pressure and leak tests on the ground.
The test ports are connected through tubes to the LP distribution manifolds (5753HM1 and 5753HM2).
Two test ports (5755HM1 and 5755HM2) are used for the pressure and leak tests on the ground.
The test ports are connected through tubes to the LP distribution manifolds (5753HM1 and 5753HM2).
C. Indicating
(1) HP Oxygen Indicator
The HP oxygen value is shown on the direct-reading pressure gage of the valve assembly of the crew oxygen-storage cylinder.
There is no compensation in temperature for this HP value.
The HP oxygen value is shown on the direct-reading pressure gage of the valve assembly of the crew oxygen-storage cylinder.
There is no compensation in temperature for this HP value.
(2) Overboard discharge indicator (5756HM)
The oxygen circuit has an overboard discharge line.
If there is too much pressure in the HP or in the LP oxygen circuit, the overpressure is released out of the aircraft through an overboard discharge line.
When the overpressure flows into the outer side, the green disc (that you can usually see on the overboard discharge indicator, out of the aircraft) breaks and a yellow reflective area replaces the green disc.
The overboard discharge indicator is installed between FR12 and FR13, on the left side.
The green disc breaks at a pressure between 40 psi (2.76 bar) and 100 psi (6.89 bar).
The oxygen circuit has an overboard discharge line.
If there is too much pressure in the HP or in the LP oxygen circuit, the overpressure is released out of the aircraft through an overboard discharge line.
When the overpressure flows into the outer side, the green disc (that you can usually see on the overboard discharge indicator, out of the aircraft) breaks and a yellow reflective area replaces the green disc.
The overboard discharge indicator is installed between FR12 and FR13, on the left side.
The green disc breaks at a pressure between 40 psi (2.76 bar) and 100 psi (6.89 bar).
(3) Overboard discharge indicators (5756HM1 and 5756HM2)
Each oxygen circuit has an overboard discharge line.
If there is too much pressure in the HP or in the LP oxygen circuit, the overpressure is released out of the aircraft through an overboard discharge line.
When the overpressure flows into the outer side, the green disc (that you can usually see on the overboard discharge indicator, out of the aircraft) breaks and a yellow reflective area replaces the green disc.
The overboard discharge indicator of the Captain oxygen circuit is between FR12 and FR13, on the left side.
The overboard discharge indicator of the First Officer oxygen-circuit is between FR17 and FR18, on the left side.
The green disc breaks at a pressure between 40 psi (2.76 bar) and 100 psi (6.89 bar).
Each oxygen circuit has an overboard discharge line.
If there is too much pressure in the HP or in the LP oxygen circuit, the overpressure is released out of the aircraft through an overboard discharge line.
When the overpressure flows into the outer side, the green disc (that you can usually see on the overboard discharge indicator, out of the aircraft) breaks and a yellow reflective area replaces the green disc.
The overboard discharge indicator of the Captain oxygen circuit is between FR12 and FR13, on the left side.
The overboard discharge indicator of the First Officer oxygen-circuit is between FR17 and FR18, on the left side.
The green disc breaks at a pressure between 40 psi (2.76 bar) and 100 psi (6.89 bar).
(4) CREW SUPPLY pushbutton switch (2HT)
When the distribution circuit(s) operates (operate), the white OFF legend of the CREW SUPPLY pushbutton switch goes off.
When the distribution circuit(s) is (are) closed, the white OFF legend of the CREW SUPPLY pushbutton switch comes on.
When the distribution circuit(s) operates (operate), the white OFF legend of the CREW SUPPLY pushbutton switch goes off.
When the distribution circuit(s) is (are) closed, the white OFF legend of the CREW SUPPLY pushbutton switch comes on.
D. Lower ECAM DU
(1) On the lower ECAM display unit, on the DOOR/OXY page, the oxygen pressure in the cylinder is shown as follows:
(a) Less than 27.5 bar (399 psi) in amber
(b) From 27.5 bar (399 psi) to 127.5 bar (1850 psi) in green
(c) An amber half frame comes into view when the oxygen pressure is less than 103.42 bar (1500 psi).
(2) On the lower ECAM DU, on the DOOR/OXY page, the oxygen pressure in the cylinder is indicated as follows:
(a) Less than 27.5 bar (399 psi) in amber.
(b) From 27.5 bar (399 psi) to less than 55.2 bar (801 psi) pulses in green.
(c) Equal to or more than 55.2 bar (801 psi) in green.
(d) An amber half frame shows when the oxygen pressure is lower than 103.42 bar (1500 psi).
(3) On the lower ECAM DU, on the DOOR/OXY page, the oxygen pressure in the cylinder is indicated as follows:
Crew Oxygen System - ECAM Data ** ON A/C NOT FOR ALL
Crew Oxygen System - ECAM Data ** ON A/C NOT FOR ALL
Crew Oxygen System - ECAM Data ** ON A/C NOT FOR ALL Crew Oxygen System - ECAM Data ** ON A/C NOT FOR ALL (a) Less than 20.6 bar (299 psi) in amber.
(b) From 20.6 bar (299 psi) to less than 41.2 bar (598 psi) pulses in green.
(c) Equal to or more than 41.2 bar (598 psi) in green.
(d) An amber half frame shows when the oxygen pressure is lower than 68.94 bar (1000 psi).
(4) On the DOOR/OXY page of the lower ECAM DU, on the upper right part, you can see the indications that follow:
(a) HP values of the crew oxygen-storage cylinder(s)
There is no compensation in temperature for these HP values. These HP values come into view in:
There is no compensation in temperature for these HP values. These HP values come into view in:
- Green when they are equal to or more than 500 psi (34.47 bar).
- Pulsing in green when the values are between 200 psi (13.79 bar) and 499 psi (34.40 bar).
- Amber when the values are less than 200 psi (13.79 bar).
(b) Amber Half-box
There is an amber half-box around the HP oxygen value of the applicable crew oxygen-storage cylinder, in the two conditions that follow:
There is an amber half-box around the HP oxygen value of the applicable crew oxygen-storage cylinder, in the two conditions that follow:
- The HP oxygen value is less than 800 psi (55.16 bar), and
- The aircraft is in flight phase 1, 2, 9 or 10.
NOTE: If the Flight Warning Computer (FWC) is not valid, the amber half-box is shown in all the flight phases.
(5) REGUL LO PR Message
If the oxygen pressure drops below the minimum operating pressure of 3.45 +-0.35 bar or -+0.35 bar (50 +-5 psi or -+5 psi), the indication REGUL LO PR is shown amber on the DOOR/OXY page.
If the oxygen pressure drops below the minimum operating pressure of 3.45 +-0.35 bar or -+0.35 bar (50 +-5 psi or -+5 psi), the indication REGUL LO PR is shown amber on the DOOR/OXY page.
(6) REGUL (1), (2) or (1+2) LO PR Message
This message comes into view in amber below the HP oxygen values in the two conditions that follow:
If only LP switch 4WV1 operates, the REGUL 1 LO PR message comes into view.
If only LP switch 4WV2 operates, the REGUL 2 LO PR message comes into view.
If the two LP switches (4WV1 and 4WV2) operate, the REGUL 1+2 LO PR message comes into view.
This message comes into view in amber below the HP oxygen values in the two conditions that follow:
- One and/or two LP switches (4WV1 and/or 4WV2) operate(s) and send(s) an LP oxygen status to the ECAM, and
- The LP oxygen status stays for five seconds.
If only LP switch 4WV1 operates, the REGUL 1 LO PR message comes into view.
If only LP switch 4WV2 operates, the REGUL 2 LO PR message comes into view.
If the two LP switches (4WV1 and 4WV2) operate, the REGUL 1+2 LO PR message comes into view.
(7) OXY Legend
In normal condition, the OXY legend is green.
The OXY legend becomes amber if:
In normal condition, the OXY legend is green.
The OXY legend becomes amber if:
- The LP switch (4WV) senses an LP oxygen status, or
- The LP oxygen-supply solenoid valve (3HT) is closed (It is closed if the CREW SUPPLY pushbutton switch (2HT) is in the OFF position), or
- The HP oxygen value is less than 400 psi (27.58 bar), or
- The HP oxygen value is not available and is replaced an amber XX legend.
(8) CKPT OXY Legend
In normal condition, the CKPT OXY legend is white.
The CKPT OXY legend becomes amber if:
In normal condition, the CKPT OXY legend is white.
The CKPT OXY legend becomes amber if:
- The LP switches (4WV1 and/or 4WV2) sense an LP oxygen status, or
- The LP oxygen-supply solenoid valves (3HT1 and 3HT2) are closed (they are closed if the CREW SUPPLY pushbutton switch (2HT) is in the OFF position), or
- A minimum of one HP oxygen value is less than 200 psi (13.79 bar), or
- A minimum of one HP oxygen value is not available and is replaced with an amber XX legend.