The basic components of the OBOGS are the
concentrator, oxygen monitor, and control panel
The oxygen concentrator (fig. 7-18) produces an
oxygen-rich gas by processing engine bleed air through
two sieve beds. It is an electrical/mechanical device that
is made up of a rotary valve, two molecular sieve beds,
drive/servo motor, plenum assembly, air heater, inlet
filter, over-temperature sensor indicator, pressure
reducer, and insulating shroud.
The oxygen monitor (fig. 7-19) senses the partial
pressure of the gas and if necessary, provides a
low-pressure warning to the pilot. It is an electronic
Figure 7-19.--Oxygen monitor.
processor made up of an oxygen sensor, processing
electronics, built-in test (BIT), a circuit heater, and a
pressure-controlled sensing chamber.
· OBOGS ON/OFF control switch (electrical)
· OXY FLOW ON/OFF control valve (mechan-
Control Panel Assembly
The control panel assembly (fig. 7-20) houses the
controls to operate the OBOGS system. It contains the
Figure 7-20.--Control panel assembly.
Figure 7-18.--Oxygen concentrator.