HOBO Dissolved Oxygen Logger (U26-001) Manual
© 2012–2014 Onset Computer Corporation. All rights reserved. Onset, HOBO, and HOBOware are
trademarks or registered trademarks of Onset Computer Corporation.
RDO is a registered
trademark of In-Situ® Inc., Fort Collins, CO USA.
All other trademarks are the property of their
respective companies.
15603-E MAN-U26x
3.
Remove the logger from the water and read out the data
from the logger using a shuttle or computer with a base
station.
4.
If you are deploying it again, clean the sensor (see
Maintenanc
e for details).
5.
Check the expiration date for your cap and make sure it will
not expire before the end of your deployment. Replace it if
needed.
6.
Relaunch the logger if it is not already logging.
7.
Take another field calibration reading after the logger is
cleaned.
8.
Redeploy the logger.
Using the HOBOware Dissolved
Oxygen Assistant
Use the Dissolved Oxygen Assistant to obtain accurate
Dissolved Oxygen readings if the logger was deployed in a
saltwater environment or if percent saturation is required. Also
use this assistant if you took field calibration readings. The
Dissolved Oxygen Assistant is only available in HOBOware from
the Plot Setup window when you open a file from this logger.
To use the assistant:
1.
Offload the most recent data files from the shuttle or logger
to your computer.
2.
Open a data file in HOBOware.
3.
In the Plot Setup window, select the Dissolved Oxygen
Assistant and click Process.
4.
In the Dissolved Oxygen Assistant window, enter the
salinity, barometric pressure, and field calibration
information as needed. Click the Help button in the
Dissolved Oxygen Assistant for more details and to learn
about the ranges of input data allowed.
5.
Plot the data and save it as a project file.
Maintenance
To clean the sensor cap:
1.
Remove the protective guard or anti-fouling guard, but
leave the sensor cap on the sensor.
2.
Rinse the logger with clean water from a squirt bottle or
spray bottle.
3.
Gently wipe the cap with a soft-bristled brush (such as a
toothbrush) or soft cloth if biofouling is present. Use
Alconox® to remove grease.
4.
If extensive debris or mineral build-up is present, soak the
cap end in vinegar for 15 minutes, then soak it in deionized
(DI) water for another 15 minutes.
5.
If the logger is being immediately redeployed with the same
sensor cap, a field calibration is adequate. If a new sensor
cap is being installed, a lab calibration with HOBOware is
recommended. When storing the logger between
deployments, keep it in the calibration boot (wet the small
sponge with fresh water, place the sponge in the end of the
calibration boot, and then insert the logger in the boot.)
WARNING:
Do not use organic solvents; they will damage
the sensor. Do not remove the sensor cap from the sensor prior
to cleaning with a brush. Only clean the sensor when you
replace the sensor cap. See the full instructions that ship with
the replacement sensor cap. Do not wet the sensor optical lens
area with water or any solution. Remove the cap and gently
wipe the window with a soft cloth.
To clean the logger body:
1.
Make sure the sensor cap is installed on the logger.
2.
Gently scrub the logger body with a plastic bristle brush or
nylon dish scrubber.
3.
Use Alconox® to remove grease.
4.
Soak in vinegar to remove mineral deposits.
5.
Rinse the logger with deionized (DI) water.
Battery Guidelines
The battery life of the logger should be three years or more.
Actual battery life is a function of the number of deployments,
logging interval, and operation/storage temperature of the
logger. Frequent deployments with fast logging intervals,
continuous storage/operation at temperatures above 35°C
(95°), and keeping the logger connected to the coupler will
result in significantly lower battery life. For example, the
battery may last less than a year with a 1-minute logging
interval. To obtain a three-year battery life, a logging interval of
five minutes or greater should be used and the logger should be
operated and stored at temperatures between 0° and 25°C (32°
and 77°F).
The logger can report and log its battery voltage. If the battery
falls below 3.2 V, the logger will record a “bad battery” event in
the datafile. The logger will record a second “bad battery”
event and stop logging when the battery falls below 3.1 V. If the
datafile contains “bad battery” events, the logger should be
returned to Onset for battery replacement. Note the logger
does not have to be recording the battery channel for it to
detect bad battery events. The logger will record these events
regardless of what channels are logged. To have your logger’s
battery replaced, contact Onset or your place of purchase for
return arrangements. Do not attempt to replace the battery
yourself. Severe damage to the logger will result if the case is
opened without special tools, and the warranty will be voided.
WARNING:
Do not cut open, incinerate, heat above 100°C
(212°F), or recharge the lithium battery. The battery may
explode if the logger is exposed to extreme heat or conditions
that could damage or destroy the battery case. Do not dispose
of the logger or battery in fire. Do not expose the contents of
the battery to water. Dispose of the battery according to local
regulations for lithium batteries.
