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Fluorometer Mode
The Fluorometer Mode should be selected if a Turner Fluorometer is being used. This will change
the 1-Point Calibration to make it easy to adjust the ppm reading of the chemical product based on
measurement of the fluorescent dye.
To select this transmitter as fluorometer, click the Enable radio button, then click on the Submit
button at the bottom of the page.
Backup Sensor Mode
The redundant sensor algorithm will allow the user to define a primary sensor to use for control
and a backup sensor. If the primary sensor goes invalid, the backup sensor will automatically take
over control, and the sensor error alarm will activate. If the sensors don’t match each other within
user-defined limits but both are valid readings, control will stop and a Sensor Deviated alarm will
activate. If the backup sensor goes invalid while the primary sensor is OK, control continues but
the sensor error alarm will activate. If both sensors are invalid, control stops and the sensor error
alarms activate.
To select this sensor as the backup sensor, click the Backup radio button, then click on the Submit
button at the bottom of the page. The page will reload showing the status of the sensor as Backup,
and offer additional menus:
Primary Sensor Assignment
This menu only appears if the Redundant Sensor Setting is Backup.
Use the pulldown arrow to select the sensor to use as the primary control sensor. All sensors of the
same type as the backup sensor will appear in the pulldown list.
Deviation from Primary Sensor
This menu only appears if the Redundant Sensor Setting is Backup.
Type the maximum allowable difference between the two sensor readings. If this deviation is
exceeded, then control of any outputs using the sensor will stop and an alarm activated.
6.11 4-20 mA Input Menu
This page is used to assign the purpose of each 4-20 mA input and to calibrate each input.
Status
Possible status messages are Normal (everything is OK), Sensor Error (the sensor signal is not
valid), Over Range (between 20 and 21 mA), Under Range (between 3.9 and 4.0 mA), High
Alarm, Low Alarm or Circuit Board Failure. See section 8.1 for a complete description of error
messages.
4-20 mA Input Assignment Menu
This table is used to reassign the function of the device connected to the input. Click on the pull-
down that best describes what is connected to the input. If you assign the inputs on this page, you
need to click on the Submit button to see the appropriate menu selections on the page. These are
normally already defined in the Start up page.
Not Used
should be selected if nothing is connected to that input.
