cootwo User Manual – Rev. 20170512 ©2017 DiveNav, Inc. – www.divenav.com
P a g e 5
If you try to access the Main Settings menu while the
analyzer is connected to a smartphone, the analyzer will
display a warning screen and will give you the option to
disconnect from the smartphone.
This image on the right shows the
Main Settings menu.
This menu contains 5 sub-menus:
BACK, O2 CAL, SENSOR, LIGHT and
DATE.
To access a sub-menu first position the > pointer on the
line you want to select by as many PUSH as required then
enter the sub-menu by a HOLD.
If you HOLD when BACK is selected you will go back to
the previous menu. In the case of the image above you will
go back to the Normal Operating Mode.
The S symbol on the top row indicates that you are in
the settings operating mode.
The O2 CAL sub-menu allows you to perform an
Oxygen sensor calibration.
The SENSOR sub-menu allows you to access settings
for either the Oxygen sensor or the Carbon Monoxide
sensor.
The LIGHT sub-menu allows you to program intensity
and duration of the backlight.
The DATE sensor allows you to program date and time.
Please note that the settings available in stand-alone
mode are a sub-set of the full set of settings available with
the My Nitroxbuddy app.
See below the top level view of cootwo menus.
7 OXYGEN SENSOR
cootwo comes equipped with an electrochemical
Oxygen sensor. The life of an Oxygen sensor is difficult to
estimate as it might be affected by several factors such as
usage, exposure to a gas with high content of Oxygen,
temperature and humidity.
Also, an Oxygen sensor does not die immediately but
slowly degrades over time.
We recommend to replace the factory installed Oxygen
sensor every 12 months. But, if you are in the middle of a
dive trip you can simply extend the life of the O2 sensor by
simulating a replacement either in stand-alone mode or via
the My Nitroxbuddy app.
Please note that it is
YOUR
responsibility to set the
sensor life correctly. The analyzer only provides you a
reminder but it has absolutely no knowledge if the lifetime
you entered is correct for the O2 sensor you are using.
7.1
O2 Sensor Calibration
As indicated earlier, with cootwo you can perform an
Oxygen sensor calibration either with the stand-alone unit or
with the assistance of a smartphone.
To calibrate the Oxygen sensor while in stand-alone
mode, first turn the unit ON.
Then, while the unit is in the Normal Operating Mode,
HOLD the button and enter the Main Settings menu.
Now, PUSH the button to position
the pointer on the O2 CAL sub-menu as
per image on the right.
Now, HOLD the button to enter the
Oxygen Sensor calibration sub-menu
show in the image on the left.
As indicated earlier, HOLD enters the sub-menu
selected by the pointer while a PUSH moves to the next line
down. In this specific case, HOLD will go back to the
previous menu while PUSH will start the calibration of the
Oxygen sensor.
During an Oxygen sensor calibration it is very important
to expose cootwo to a known source of gas flowing at a
constant rate.
WARNING: If you plan to perform an Oxygen sensor
calibration by exposing cootwo to ambient air MAKE
SURE cootwo acclimates for at least 5 minutes as the
gas flow within the device is reduced and a shorter
period might produce incorrect results.
Now, position your cootwo in front of the valve of a
scuba tank containing air and open the tank valve slowly so
to limit the gas flow to few liters per minute. If you have
ordered the Low Pressure Inflator adapter then you can
connect your cootwo directly to the low pressure hose.
Once you are ready PUSH the activation button to start
the Oxygen sensor calibration and cootwo will alternate the
2 screens below until the O2 calibration is completed.
As mentioned above, the stand-alone, manual Oxygen
calibration is limited to air, it is time based and it takes about
one minute.