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MODEL 54eA SECTION 15.0
TROUBLESHOOTING
SECTION 15.0TROUBLESHOOTING

15.1 OVERVIEW

The 54eA controller continuously monitors itself and the sensor for faults. When the controller detects a fault in the
amperometric or pH sensor or in the instrument itself it displays a fault message. If alarm 4 was enabled, the red
FAIL LED will also light and relay 4 will activate. The outputs will go to 22.00 mAor to the value programmed in
Section 5.6.
Special rules apply to pH sensor diagnostics (high and low glass impedance). Alarm 4, the FAILLED, and the out-
put current failure mode will operate only if pH sensor diagnostics have been enabled. See Section 5.8.
See Section 15.2 for an explanation of fault messages and suggested corrective actions.
The controller also displays error and warning messages if a calibration is seriously in error. Refer to the section
below for assistance. Each section also contains hints for correcting other measurement and calibration problems.
For troubleshooting not related to measurement problems, see Section 15.10.
To view diagnostic variables, go to the main display and press any key. Move the cursor to “Diagnostic variables”
and press Enter (F4). Use the or key to move up or down the list.
Measurement Section
Temperature 15.3
Dissolved oxygen 15.4
Free chlorine 15.5
Total chlorine 15.6
Monochloramine 15.7
Ozone 15.8
pH 15.9

15.2 TROUBLESHOOTING WHEN A FAULT MESSAGE IS SHOWING

Fault message Explanation See Section
High input current input current exceeds 210 uA 15.2.1
Check sensor zero sensor current was too high when sensor was zeroed 15.2.2
pH low input voltage input voltage is less than -1400 mV 15.2.3
pH high input voltage input voltage exceeds 1400 mV 15.2.3
pH low reference voltage input voltage is less than -1600 mV 15.2.4
pH high reference voltage input voltage exceeds 1600 mV 15.2.4
Old glass warning glass impedance exceeds high limit 15.2.5
Cracked glass failure glass impedance is less than low limit 15.2.6
Temp error low temperature less than -15°C 15.2.7
Temp error high temperature greater than 130°C 15.2.7
Sense line open RTD sense line is open 15.2.8
Failure factory instrument needs factory calibration 15.2.9
Failure eeprom write verify error has occurred 15.2.9