To test the EDS unit for readiness follow these steps:
If the EDS unit fails these simple tests, please be sure that you
have a fresh battery installed, that your supply of oxygen is
indeed connected and all tubes are connected correctly and not
plugged, pinched or kinked. If you cannot remedy any
dysfunctions please return the unit to Mt. High for a prompt
repair or replacement.
1:
Without an oxygen supply, but with a standard nasal
cannula connected to the larger outlet tube (blue
connector), turn on unit and let it initialize, about 8 to 10
seconds. It may or may not beep and show the red light
for about 4 seconds.
2:
The EDS should respond with the flow fault alarm each
time you inhale through the cannula and while the mode
switch is in position 'N'. Nothing should happen if you
have the mode switch in the 'D' position and are below a
pressure altitude of about 11,500 ft.
3:
With the XCR regulator mounted to a cylinder with
oxygen, connect the XCR regulator to the smaller inlet
(red connector) via the 4 mm. service line and turn on the
oxygen valve.
4:
The EDS should respond with a short pulse of oxygen
each time you inhale through the cannula while the mode
switch is in position 'N'. Nothing should happen if you
have the mode switch in the 'D' position and are below a
pressure altitude of about 11,500 ft.
To test the battery installed
in an EDS unit, follow these steps:
1:
Turn on unit and let it initialize, about 8 to 10 seconds. It
may or may not beep.
2:
While holding down the battery test button observe the red
light and beeper.
The battery test button places a load on the battery many times
more than the EDS does in normal operation and should catch a
battery that will fail in the next few hours of use. The EDS unit
may still operate for a few hours even if the battery test has
indicated low, but you may be taking an unnecessary risk of
total failure at an inconvenient time. Be sure to use a well
known brand alkaline type battery. Do not use carbon/zinc
type batteries; they have a shorter life and fail in the cold.
A standard nine volt alkaline battery may last up to 40 hours.
This will depend on the ambient temperature. The EDS has an
audible/visual low battery indicator, giving plenty of time
before exhaustion and the (No-Flow) alarm to signal that the
oxygen supply is either off or has run out. The F-2 face mask
kit can be optionally used as an emergency supply by-pass in
the event of a total EDS system failure. See application notes
later in this manual.
For health reasons, each person using the system should have
their own nasal cannula and face mask. In addition,
replacement of the nasal cannula should be done if it has
become soiled or damaged in any way.
The flow fault alarm will respond
to the following actions or reasons:
1:
If you inhale on the system without a supply of oxygen
2:
If you try to inhale from the system directly without
adding ambient air (over demand) the EDS will not deliver
a sufficient volume of air and oxygen.
3:
If the battery powering the EDS unit is too low to operate
the micro-valve.
The red & green lights on the EDS unit are complemented via
the audio beeper. If you run out of oxygen while in flight the
beeper will sound with each breath. At any time you could test
the readiness of the EDS simply by pressing the battery test
button during use. Observation of the lights are not actually
required for operation. The EDS responds to pressure altitude
and not MSL. or AGL. Therefore, while operating in "D"
mode the unit will not commence operation precisely at the
same pressure altitude on a day-by-day or location basis. This
is because atmospheric pressure is constantly changing with
time and distance. In addition, while operating a dual or multi-
place EDS system in "D" mode you may notice that not all
units will commence operation precisely at the same pressure
altitude. They may differ by as much as 500 ft. This is well
within calibration tolerance. If the EDS unit is to be operated
in a pocket or pouch, it is possible that the unit will false-
trigger. This is because a pocket or pouch may act as a flask
causing differential pressures to occur between the unit and
cannula or face mask. Make sure that the pocket or pouch is
not sealed in a near air-tight fashion. If this can not be
avoided you can tape a small plastic tube near the static port on
the EDS unit and run it to the outside of the pocket or pouch to
eliminate any possible differential pressures caused by
confinements in a pocket or pouch. If false-triggering due to
the flask effect cannot be corrected, the EDS unit should be
operated uncovered mounted via the EDS holster harness kit.
To replace the battery:
Remove battery door by holding the unit with both hands and
pressing in with thumbs at the point of the arrow while pushing
door outwards (fig 1) This is best done if the unit is held with
the battery door facing you and out. The EDS model "A" uses
a standard 9 volt alkaline battery connector system. This is an
aggressive type of battery connector requiring a bit more force
to connect and disconnect to the battery. This is a superior type
connector for equipment subjected to rough out-door treatment.
Therefore, please take extra care in removing and replacing the
battery. Use only alkaline type batteries with the EDS unit.
