MN301905 Rev A
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Appendix (continued)
Step Ten
FALSE ECHO
Obstructions in the tank (mixer blades, side wall weld joints or material build-up,
submersible pumps, piping, other apparatus) or tall tank risers or installation fittings
can create false echo returns that impair the sensor’s measurement. This function
maps all echo returns within the tank, differentiating between good and false echoes,
and stores those identified as false into the False Echo Curve, so they will not be considered in the level
measurement.
Note: A False Echo Curve should only be performed when the tank is empty so that all false
reflections will be detected.
This function allows the selection of the below False
Echo Curve settings:
Delete - Used to remove a stored False Echo Curve.
Update - Used to update a stored False Echo Curve.
Note
:
Do not use this function to update an existing False Echo Curve when the level is above the original
False Echo Curve.
Create New - Used to create a new False Echo Curve.
Edit - Used to edit the false
echoes stored in a False
Echo Curve.
Note: This
function should only be
performed by a trained
technician.
OUTPUT SETTINGS
This function allows the selection of the below of 4-20mA Reverse, Fail-Safe and
Minimum Current output settings. The initial screen indicates the status of the three
functions.
4-20 mA Reverse - Used to set the current output at 4-
20 mA or 20-4 mA. Selecting 4-20 mA sets the output
with 4mA @ bottom and 20mA @ top of the tank.
Selecting 20-4 mA sets the output with 20mA @ bottom
and 4mA @ top of the tank.
Default is 4-20mA.
Fail-Safe – Used to set the current output to a
designated if the sensor loses measurement
confidence. Selecting No Change will hold the current
at its last valid current output. Selecting 20.5mA will
force the current to jump to 20.5mA. Selecting 22.5
mA will force the current to jump to 22.5 mA.
Default
is 22.0mA.
Minimum Current - Used to set the minimum current
output at either 4.0mA or 3.9mA.
Default is 4.0mA.
