10
11
If the DO% measurement is incorrect in a water-saturated air
environment (BOD bottle with 40 ml of clean water) after calibration,
ensure the instrument’s barometer reading is correct by comparing it
to the local, true barometric pressure.
If you continue to have erroneous DO readings, verify the sensor is
properly connected to the instrument. If using the ProODO instrument,
be sure DO is enabled in the Probe menu. Next, clean the sensor cap
following the instructions in the
Maintenance and Storage
section of
this manual and then perform a calibration. If erroneous readings persist,
follow the steps on the following page to inspect the sensor cap for
damage and then attempt to recalibrate the instrument. If the problem
continues, try to rehydrate the sensor cap and then recalibrate. If you
are still getting erroneous dissolved oxygen readings, try replacing the
sensor cap and then recalibrate. If the erroneous readings continue,
contact YSI Technical Support to help determine the next step.
INSPECTING ThE SENSOR CAP FOR DAMAGE
Caution: Avoid touching the sensing end of the sensor
cap during the following maintenance procedures.
If DO measurements seem to be in error or are jumpy, remove the
sensor cap from the sensor by grasping the probe body with one hand
and then rotating the sensor cap counterclockwise until it is completely
free. Do not use any tools for the removal of the cap.
Inspect the sensor cap assembly for any cracks or damage. If damage
has occurred, contact YSI Customer Service to order a replacement
sensor cap (YSI item number 626482).
Inspect the o-ring on the probe for damage. If there is any indication of
damage, carefully remove the o-ring and contact YSI Technical Support
to obtain a new o-ring and/or gasket. Avoid using tools to remove the
o-ring as damage to the sealing surfaces could result.
Before reinstalling the sensor cap, make sure that the cavity is
completely clean and dry before proceeding with the installation. If
water is found, dry the cavity with lens tissue. Finally, clean and dry the
clear optical DO sensor window on the end of the sensor with a lens
tissue.
After reinstalling the sensor cap, perform a calibration and then
reevaluate the quality of the dissolved oxygen measurements. If
problems persist, try rehydrating or replacing the sensor cap.
errOr/StatUS meSSageS
While using of the ProODO instrument, press the
Question
key
from any screen to view helpful messages directly on the display.
Refer to the instrument manual for information on error and status
messages.
P R O B E S P E C I F I C A T I O N S
The specifications listed below are system specifications for the
ProOBOD probe when used with a ProODO instrument. These
specifications are subject to change without notice. For the most
recent specifications and for specifications on the ProODO instrument,
please visit ysi.com.
Probe (ProOBOD probe and cable Assembly)
Temperature
Operating Range
10 - 40°C
Water Resistance IP-65
Cable Length
2 meters (6.56 feet)
Dissolved Oxygen
Sensor Type
Optical, Life-time Luminescent sensor
Range
0-50 mg/L
0-500 % Saturation
Accuracy (mg/L) • 0 to 20 mg/L: ± 0.1 mg/L or ± 1%
of reading, whichever is greater.
• 20 to 50 mg/L: ± 15% of the reading
Accuracy
(% Saturation)
• 0 to 200% air saturation: ± 1% of the reading
or ± 1% air saturation, whichever is greater.
• 200 to 500% air saturation: ± 15% of the read-
ing
Resolution
(mg/L)
0.01 or 0.1 mg/L (auto-scaling)
Resolution (%
Saturation)
0.1% air saturation
Response Time
T95 = 20-25 seconds with stirring;
T95 = 40 seconds without stirring.