Sensor Performance Problems - YSI 6 series User Manual

Troubleshooting

6.3 SENSOR PERFORMANCE PROBLEMS

SYMPTOMS
Rapid Pulse dissolved
Oxygen reading
unstable or inaccurate
ROX dissolved Oxygen
reading unstable or
inaccurate
pH, ORP, chloride,
ammonium, or nitrate
readings are unstable or
inaccurate. Error
messages appear during
calibration.
YSI Incorporated Environmental Monitoring Systems Operations Manual
POSSIBLE CAUSE
Probe not properly calibrated
Membrane not properly installed or
may be punctured
DO probe electrodes require
cleaning
Water in probe connector
Algae or other contaminant
clinging to DO probe
Barometric pressure entry is
incorrect
Cal at extreme temperature
DO Charge too high ( >75)
1. Anodes polarized (tarnished)
2. Probe left on continuously
DO Charge too low (<25)
Insufficient electrolyte.
DO probe has been damaged
Internal failure
Probe not properly calibrated
Membrane assembly not properly
installed or may be punctured
Water in probe connector
Algae or other contaminant
clinging to DO probe
Barometric pressure entry is
incorrect
Membrane assembly is more than
1 year old
Wiper is not parking correctly
DO probe has been damaged
Probe requires cleaning,
Probe requires calibration
pH probe reference junction has
dried out from improper storage.
ACTION
Follow DO cal procedures
Follow 6562 setup procedure
Follow DO cleaning procedure.
Use 6035 maint. kit
Dry connector; reinstall probe
Rinse DO probe with clean water
Repeat DO cal procedure
Recal at (or near) sample
temperature
Enable DO charge parameter in
the Sonde report menu. Run
sonde, if charge is over 100,
recondition probe with 6035
Maintenance Kit. Follow DO
cleaning procedure.
Replace electrolyte and
membrane.
Replace 6562 probe
Return sonde for service
Follow DO cal procedures
Follow instructions for proper
membrane assembly replacement
Dry connector; reinstall probe
Rinse DO probe with clean water
Repeat DO cal procedure
Replace membrane assembly
(6155 Optical DO Membrane
Replacement Kit)
Make certain that setscrew is
tight. If problem persists, return
probe for service.
Replace 6150 probe
Follow probe cleaning procedure
Follow cal procedures
Soak probe in tap water or buffer
until readings become stable
Section 6
REF
2.6.1
2.3.1
2.10.2
2.3.2
2.10.2
2.6.1
2.6.1
2.10.2
2.3.1
9
9
2.6.1
2.10.2
2.3.2
2.10.2
2.6.1
9
9
9
2.10.2
2.6.1
2.10.2
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3