Xylem 6-Series Multiparameter - Manual (Page 285)

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