YSI ProOBOD - Manual (Page 6)

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P r o O B O D O P E R A T I O N
cOnnecting prOBe/caBle assemBly tO instrUment
To connect the cable, align the keys on the cable connector to the slots on the
instrument connector. Push together firmly, then twist the outer ring until it
locks into place (Figure 2). This MS-8 (Military Spec) connection is water-
proof.
Figure 2. Note the keyed connector. The cable and instrument connectors
can only be mated once the keyed sections are properly aligned.
cOnfigUring the p
ro
ODO instrUment
On the ProODO instrument, press the Probe key. Highlight DO and press
enter. Enabled allows you to enable or disable the DO sensor. Highlight Enabled
and press enter to activate or deactivate the dissolved oxygen sensor.
The DO Setup menu also displays the OBOD probe’s SW Version and Serial #.
This information is programmed into the probe at the factory and digitally sent
to the instrument when the cable is connected.
Within the DO Probe Setup menu, the Sensor Cap submenu allows you
to view and enter information specific to the sensor cap installed on the
probe. Highlight Sensor Cap and press enter to view the sensor cap’s Serial #,
Temperature Coefficient, and Sensor Cap Coefficients. This information is also
programmed into the probe at the factory and sent to the instrument when the
cable is connected.
The Sensor Cap Coefficients need to be updated when the sensor cap is replaced.
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. See the Sensor Maintenance - Dissolved Oxygen section of
this manual or the instruction sheet included with the replacement sensor cap
for instructions on updating the Sensor Cap Coefficients. When updating the
Coefficients, the sensor cap serial # will be updated automatically based on your
entries.
The Temperature Coefficient should not be modified unless instructed by YSI
Technical Support.
For additional information about the ProODO’s menus and operation, please
refer to the ProODO User Manual.
pOwering the stirrer
To power the stirrer, locate the power supply that was included with the
ProOBOD. The power supply for the USA/Japan probe is labeled model number
6260. The power supply for the international probe is labeled model number
6261. Next, connect the power supply to the probe’s power connector and then
plug the power supply into an outlet. The international ProOBOD is shipped
with outlet adapters to connect the power supply to a variety of outlets. The
stirrer can be turned on and off with the toggle switch located at the top of the
probe (Figure 1).
caliBratiOn - DissOlveD Oxygen
The ProOBOD sensor is an optical luminescent sensor which has greater stability
and is less susceptible to calibration drift than traditional electrochemical
sensors. This increased stability means that the instrument may hold its
calibration for many months. However, for the highest data accuracy, YSI
recommends verifying the instrument’s calibration on a daily basis. To verify
the instrument’s calibration, place the sensor in its calibration environment and
check to see that the DO% is reading its calibration value based on the current
barometric pressure. Refer to Appendix A for a list of DO% calibration values
and corresponding barometric pressure readings.
The ProODO instrument with ProOBOD probe offers several options for
performing a dissolved oxygen calibration. For both ease of use and accuracy,
YSI recommends performing a DO % water-saturated air calibration as described
below. For information on other acceptable calibration techniques, including
how to perform a 2-point calibration with a zero solution, please refer to the
ProODO User Manual.