YSI WE KNOW ProOBOD, User Manual

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M A I N T E N A N C E A N D S T O R A G E
This section describes the proper procedures for care, maintenance and storage
of the ProOBOD probe.
Important: Do not attempt to access the probe motor
assembly or open the probe body. Doing so will void
any remaining warranty. The probe body should only
be opened by a YSI Authorized Service Center.
UpDating instrUment anD prOBe firmware
The instrument and probe firmware can be updated via www.ysi.com/software.
There you will find the new firmware files and instructions on how to update the
instrument and/or probe.
sensOr maintenance - DissOlveD Oxygen
CLEANING THE OBOD SENSOR CAP
The Sensor Cap should be kept clean since some types of fouling may consume
or produce oxygen which could affect the dissolved oxygen measurements. To
clean the Sensor Cap, gently wipe away any fouling with a lens cleaning tissue
that has been moistened with water. Do not use a coarse towel or cloth or organic
solvents to clean the Sensor Cap. Using a coarse towel or organic solvent to clean
the Sensor Cap may cause permanent damage to the cap. For example, alcohol
will dissolve the outer paint layer and other organic solvents will likely dissolve
the dye in the cap. If the sensor cap is damaged, it must be replaced.
OBOD SENSOR CAP REPLACEMENT
The frequency of sensor cap replacement is dependent on use. For example,
when the probe is powered on for approximately 4 hours per day, 5 days a week,
the sensor cap will need replaced about once per year. If the probe is powered
on more than this, the sensor cap will need replaced more often. To extend the
sensor cap’s usable life, turn the instrument off when not in use. For example,
turn the instrument off over night, but not between readings. The sensor cap
will also need replaced if it is damaged or cracked. See the Troubleshooting
section of this manual for instructions on how to determine if the sensor cap
needs replaced.
When replacing a Sensor Cap, the Sensor Cap Coefficients must be manually
updated in the ProODO instrument. The instruction sheet shipped with the
replacement OBOD sensor cap includes the calibration coefficients that are
specific to your Sensor Cap.
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IMPORTANT - Be sure to save the OBOD Sensor Cap instruction
sheet in case you need to reload the calibration coefficients.
The replacement OBOD Sensor Cap is shipped in a humidified container and
the package should not be opened until the cap is needed for use. Once the
sensor cap has been installed on the OBOD probe as described in this section, it
is important to keep the sensor in a 100% humid environment. Therefore, the
ProOBOD sensor should be stored in either a BOD bottle that contains a small
amount of clean water (approximately 40 ml) or in a BOD bottle that is filled
with clean water so the sensor cap is immersed in water, see Sensor Storage for
more information. If the sensor dries out, refer to the Rehydration procedure in
this manual for instructions on how to recondition the sensor cap.
Refer to Figure 3 below when following the instructions for replacing the cap.
Figure 3.
Caution: Avoid touching the sensing end of the sensor
cap during the following maintenance procedures.
Remove the stir paddle from the probe by pulling it straight out. 1.
Remove the old sensor cap from the probe by grasping the probe body 2.
with one hand and then rotating the sensor cap counterclockwise until it is
completely free. Do not use any tools for this procedure.
Carefully remove the o-ring and discard it. Do not use any tools to remove 3.
the o-ring.
Clean the o-ring seat on the probe by first wiping off old o-ring lubricant 4.
with a dry lens cleaning tissue. Next, clean away any build-up with a water-
moistened lens tissue and then dry with another lens tissue.
Locate the o-ring supplied in the Sensor Cap replacement kit and install it 5.
on the probe. Do not use any tools to replace the o-ring. Be careful not to
touch the clear optical DO sensor window. Any fingerprints on the optical
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O-ring
OBOD Sensor
Cap, shown
here removed
from probe
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