DOC AIRBUS | AMM A320FOXYGEN STORAGE - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
1. General
The crew oxygen-storage system has two High Pressure (HP) oxygen-cylinders that operate independently.
Each oxygen-cylinder has a valve assembly installed on its head.
A pressure regulator/transmitter is connected to each valve assembly.
Each HP oxygen cylinder and its pressure regulator/transmitter have an overboard discharge system that operates independently.
An overboard discharge system prevents too much pressure in the HP oxygen cylinders and/or in the Low Pressure (LP) chamber of the pressure regulators/transmitters.
The HP oxygen cylinders supply oxygen to the flight crew. They are installed in the left part of the avionics compartment, between frames 11 and 12 for the first oxygen cylinder and between frames 16 and 17 for the second oxygen cylinder.
Each oxygen cylinder is installed on a support that has two quick-release clamps.
** ON A/C NOT FOR ALL The crew oxygen-storage system has two High Pressure (HP) oxygen-cylinders that operate independently.
Each oxygen-cylinder has a valve assembly installed on its head.
A pressure regulator/transmitter is connected to each valve assembly.
Each HP oxygen cylinder and its pressure regulator/transmitter have an overboard discharge system that operates independently.
An overboard discharge system prevents too much pressure in the HP oxygen cylinders and/or in the Low Pressure (LP) chamber of the pressure regulators/transmitters.
The HP oxygen cylinders supply oxygen to the flight crew. They are installed in the left part of the avionics compartment, between frames 11 and 12 for the first oxygen cylinder and between frames 16 and 17 for the second oxygen cylinder.
Each oxygen cylinder is installed on a support that has two quick-release clamps.
2. Component Location
** ON A/C NOT FOR ALL 
Component Location| FIN | FUNCTIONAL DESIGNATION | PANEL | ZONE | ACCESS DOOR | ATA REF |
|---|---|---|---|---|---|
| ** ON A/C NOT FOR ALL | |||||
| 5750HM1 | OXYGEN CYLINDER | 125 | 35-11-41 | ||
| 5750HM2 | OXYGEN CYLINDER | 126 | 35-11-41 | ||
| 4HT | XMTR/PRESS REG-OXY | 125 | 35-13-15 | ||
| 4HT2 | PRESS.TRANSM.REGULATO | 126 | 35-13-15 | ||
| 5769HM1 | PORT.FILLING ASSY | 123 | 35-11-42 | ||
| 5769HM2 | PORT.FILLING ASSY | 120 | 35-11-42 | ||
| 5HT1 | IND OXY FILLING | 125 | 35-13-21 | ||
| 5HT2 | IND OXY FILLING | 125 | 35-13-21 | ||
3. System Description
In the applicable oxygen storage sub-system, the equipment with the LP oxygen-supply solenoid-valve is part of the oxygen storage sub-system.
For the oxygen storage sub-system, a fully isolated source supply line receives the LP oxygen from the pressure regulator/transmitter and supplies it to the LP oxygen-supply solenoid-valve.
The LP oxygen-supply solenoid-valve has an electrical shut-off function between the oxygen supply sub-system and the downstream crew-distribution sub-system.
The pressure regulator/transmitter decreases the HP oxygen from the HP oxygen cylinder, to a lower breathing level. oxygen cylinder and to the LP chamber of each pressure regulator/transmitter (Ref. AMM D/O 35-13-00-00).
An overboard discharge indicator is connected to crew oxygen-storage system through an overboard discharge line to release unwanted HP oxygen and/or LP oxygen.
The below information about the crew oxygen-storage system is applicable only to the aircraft which has two oxygen cylinders:
An overboard discharge indicator is connected to the crew oxygen-storage system through an overboard discharge line to release unwanted HP oxygen and/or LP oxygen.
The overboard discharge line is fully isolated from the other one.
The overboard discharge line is connected to the HP safety outlet of the each oxygen cylinder and to the LP chamber of each each pressure regulator/transmitter (Ref. AMM D/O 35-13-00-00).
Each system is mechanically isolated from the other system. Thus, if there is a malfunction in one of the systems, this will not have an effect on the other system.
In the cockpit, on overhead control and indicating panel 21VU, only the CREW SUPPLY pushbutton switch is for the two systems. Its function is to start or close the two systems at the same time.
** ON A/C NOT FOR ALL In the applicable oxygen storage sub-system, the equipment with the LP oxygen-supply solenoid-valve is part of the oxygen storage sub-system.
For the oxygen storage sub-system, a fully isolated source supply line receives the LP oxygen from the pressure regulator/transmitter and supplies it to the LP oxygen-supply solenoid-valve.
The LP oxygen-supply solenoid-valve has an electrical shut-off function between the oxygen supply sub-system and the downstream crew-distribution sub-system.
The pressure regulator/transmitter decreases the HP oxygen from the HP oxygen cylinder, to a lower breathing level. oxygen cylinder and to the LP chamber of each pressure regulator/transmitter (Ref. AMM D/O 35-13-00-00).
An overboard discharge indicator is connected to crew oxygen-storage system through an overboard discharge line to release unwanted HP oxygen and/or LP oxygen.
The below information about the crew oxygen-storage system is applicable only to the aircraft which has two oxygen cylinders:
An overboard discharge indicator is connected to the crew oxygen-storage system through an overboard discharge line to release unwanted HP oxygen and/or LP oxygen.
The overboard discharge line is fully isolated from the other one.
The overboard discharge line is connected to the HP safety outlet of the each oxygen cylinder and to the LP chamber of each each pressure regulator/transmitter (Ref. AMM D/O 35-13-00-00).
Each system is mechanically isolated from the other system. Thus, if there is a malfunction in one of the systems, this will not have an effect on the other system.
In the cockpit, on overhead control and indicating panel 21VU, only the CREW SUPPLY pushbutton switch is for the two systems. Its function is to start or close the two systems at the same time.
4. Component Description
(1) Each oxygen cylinder has the properties that follow:
(a) The oxygen cylinder is made of composite material.
(b) The oxygen cylinder has a capacity of 2183 l (576.68 USgal) (77.1 cubic feet) at a pressure of 1850 psi (127.55 bar).
(2) The applicable oxygen cylinder has a valve assembly with the components that follow:
(a) A manual slow-opening ON/OFF valve, with a metal seat and a metal poppet assembly.
When you turn the valve counterclockwise, the oxygen flows into the circuit.
When you turn the valve clockwise, the flow of oxygen in the circuit stops.
The manual valve is used during the replacement of the cylinder and/or to isolate the cylinder from the oxygen circuit.
When you turn the valve counterclockwise, the oxygen flows into the circuit.
When you turn the valve clockwise, the flow of oxygen in the circuit stops.
The manual valve is used during the replacement of the cylinder and/or to isolate the cylinder from the oxygen circuit.
(b) A direct-reading pressure gage that gives the pressure in the cylinder, independently from the open or closed position of the manual valve.
(c) A high-pressure safety outlet with a frangible disc which breaks at a pressure between 2500 psi (172.37 bar) and 2775 psi (191.33 bar). In this overpressure condition, oxygen is released into the overboard discharge line.
(1) The applicable valve assembly is connected to a pressure regulator/transmitter:
(a) The pressure regulator/transmitter has these properties:
- It decreases the oxygen pressure from the HP oxygen cylinder/valve assembly to a lower, breathing level in the distribution circuit.
- When the source supplies a pressure between 100 psi (6.89 bar) and 1850 psi (127.55 bar), the oxygen flows through the outlet at a pressure between 65 psi (4.48 bar) and 94 psi (6.48 bar).
- The maximum outlet flow is 500 l.min (132.08 USgal.mn).
(b) The pressure regulator/transmitter has the components that follow:
- A pressure sensor installed on the HP chamber of the pressure regulator/transmitter, sends an electrical signal of the oxygen pressure to the ECAM system in the cockpit.
- An LP safety outlet with an integrated LP relief valve to prevent unwanted pressure flows into the distribution circuit. The LP relief valve opens at a pressure between 109 psi (7.5 bar) and 116 psi (8.0 bar) and releases the pressure to the overboard discharge line.
- A filling connector installed on the HP chamber of the pressure regulator/transmitter, is used to connect the filling line.
C. Replenishment of the Oxygen Cylinders
If the oxygen cylinder(s) is (are) empty, you can fill it (them) through its (their) filling port(s) with an external filling source.
If the oxygen cylinder(s) is (are) empty, you can fill it (them) through its (their) filling port(s) with an external filling source.