YSI 556 MPS - Manual (Page 110)

Troubleshooting Section 13
YSI 556 MPS YSI Incorporated Page 104
PROBLEM POSSIBLE SOLUTIONS
Sensor Problems
Sensor requires cleaning. Follow sensor cleaning procedure.
Sensor requires calibration. Follow cal procedures.
pH sensor reference junction has dried out from improper
storage. Soak sensor in tap water or buffer 4 until readings
become stable.
Water in sensor connector. Dry connector; reinstall sensor.
Sensor has been damaged. Replace sensor.
Calibration solutions out of spec or contaminated with other
solution. Use new calibration solutions
ORP fails Zobell check. Take into account temperature
dependence of Zobell solution readings.
pH or ORP readings are
unstable or inaccurate. Out of
Range message appears during
calibration.
Internal failure. Return probe module for service.
Conductivity improperly calibrated. Follow calibration
procedure.
Conductivity sensor requires cleaning. Follow cleaning
procedure.
Conductivity sensor damaged. Replace sensor.
Calibration solution out of spec or contaminated. Use new
calibration solution.
Internal failure. Return probe module for service. Conductivity unstable or
inaccurate. Out of Range
message appears during
calibration
Calibration solution or sample does not cover entire sensor.
Immerse sensor fully.
Water in connector. Dry connector; reinstall sensor. Temperature, unstable or
inaccurate
Sensor has been damaged. Replace the 5560 sensor.
The sensor has been disabled. Enable sensor.
Water in sensor connector. Dry connector; reinstall sensor.
Sensor has been damaged. Replace sensor.
Report output improperly set up. Set up report output. Installed sensor has no reading
Internal failure. Return probe module for service.
If these guidelines and tips fail to correct your problem or if any other symptoms
occur, contact YSI Customer Service for Advice. Refer to Appendix E Customer
Service.