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O B O D P R O B E O P E R A T I O N
Connect the OBOD probe to the instrument. If using a ProODO
instrument, align the keys on the cable connector to the slots on the
instrument connector. If using an IDS MultiLab instrument, locate the
sensor connector and stirrer connector on the back of the instrument.
See instrument manual for more information.
The OBOD probe will automatically be recognized by the instrument.
If the sensor cap was installed on the probe at the factory, the sensor
cap coefficients are preloaded into the probe and uploaded to the
instrument when the probe is connected. If installing a new sensor
cap, the new coefficients need to be entered in the instrument. See the
instrument manual for more information.
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 IDS MultiLab instrument will enable the
probe automatically.
For additional information about the instrument’s menus, settings and
operation, please refer to the instrument’s manual.
pOwering the Stirrer
If using the IDS ProOBOD, the IDS MultiLab instrument will power the
stirrer. Simply connect the IDS ProOBOD connectors to the appropriate
connectors on the back of instrument.
If using the ProOBOD, locate the power supply that was included with
the probe. 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 OBOD 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 a water-saturated air environment (BOD bottle with 40 ml
of water) and check to see that the DO% measurement is reading its
the calibration value based on the current barometric pressure. Refer
to Appendix A for a list of DO% calibration values and corresponding
barometric pressure readings. If DO Local is turned on, the instrument
and probe will read 100% in its calibration environment.
There are several options for calibrating the OBOD sensors. For both
ease of use and accuracy, YSI recommends performing a DO % water-
saturated air calibration as described in the instrument’s manual.
temperatUre
All OBOD probes have built-in temperature sensors. Temperature
calibration is not required nor is it available.
taking meaSUrementS
The OBOD probes are designed for laboratory use, not field
use. They are not waterproof and should never be immersed
in a sample past the taper on the stem of the probe.
1. To take readings, insert the probe into the BOD sample bottle. The
DO and temperature sensors should be immersed in the sample.
2. Turn the stirrer on with the toggle switch located on the top of the
probe (Figure 1). The stirrer helps keep solids from settling at the
bottom of the sample bottle and quickens the sensor’s response.
3. Allow the temperature readings to stabilize and wait approximately
20-25 seconds for the DO readings to stabilize.
4. See the instrument manual for information on logging data and
sending data to a computer.
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 OBOD probes.
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.