Hach Chlorine Sensor, User Manual

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Troubleshooting
Diagnostic and test menu
The diagnostic and test menu shows current and historical information
about the chlorine analyzer. Refer to
Table 1 . To access the diagnostic
and test menu, push the MENU key and select Sensor Setup, Diag/Test.
Table 1 DIAG/TEST menu
Option Description
GATEWAY INFO Shows the firmware version, driver version, serial number
and boot version for the controller and the types of
sensors connected to the controller.
CAL DAYS Shows the number of days since the sensor was last
calibrated.
CAL HISTORY Shows a list of the times when the sensor was calibrated.
Push
ENTER to scroll through the entries and view a
summary of the calibration data.
RST CAL HISTORY Resets the sensor calibration history. Requires passcode.
SIGNALS Shows the sensor measurement signal value in mV.
SENSOR DAYS Shows the number of days the sensor has been in
operation.
RST SENSORS Resets the sensor days and calibration days to default.
Requires passcode.
CALIBRATION Shows the slope and offset values for chlorine and pH (if
pH sensor is used). Shows the offset value for the
temperature (if pH sensor is used).
Error list
Errors may occur for various reasons. The sensor reading on the
measurement screen flashes. All outputs are held when specified in the
controller menu. To show the sensor errors, push the MENU key and
select Sensor Diag, Error List. A list of possible errors is shown below.
Table 2 Error list for the sensor
Error Description Resolution
CL CAL
REQD A chlorine calibration and/or pH
calibration is required.
The chlorine and/or pH
measurement has changed
enough to cause a Cal Watch
alarm to occur. Refer to the
chlorine sensor manual for
more information. Calibrate the chlorine sensor
and/or pH sensor.
CL MAINT
REQD Chlorine sensor maintenance is
required.
The slope is less than 30% or
more than 300% of the default.
The default slope is
100 mV/ppm (100%). Do sensor maintenance and then
repeat the calibration, or replace
the sensor. Refer to the chlorine
sensor manual for more
information.
CL MAINT
REQD Chlorine sensor maintenance is
required.
The offset is too high (more
than ±50 mV). Do sensor maintenance and then
repeat the calibration, or replace
the sensor. Refer to the chlorine
sensor manual for more
information.
CONC
TOO LOW The chlorine signal is > 0 mV.
The potential delivered by the
sensor is outside of the range
0 to -2500 mV. A connection error occurred or
the chlorine sensor is not
polarized/equilibrated in the
sample sufficiently.
CONC
TOO HIGH The chlorine signal is less than
-2500 mV or greater than
2500 mV (by absolute value).
Warning list
A warning does not affect the operation of menus, relays and outputs. A
warning icon flashes and a message is shown on the bottom of the
measurement screen. To show the sensor warnings, push the
MENU
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