CiDRA SONARtrac HD VF-100 - Manual (Page 78)

Copyright © 2006 CiDRA Corporation Page 10-3
20638-02 Rev 01
OUTPUT CONFIG
·4-20mA CH1
HIGH END
090.0% 27.0 ft/s
Figure 60 Output Configuration Example Screen
Figure 61 4-20mA Output Set to 0 – 30 fps
Note: For a 4-20mA setting of 0-100%, the system Low Flow Cut Off
of 3.0 fps, from the 4–20 mA output will be 5.6mA. At flows less than
3.0 fps, greater than 30.0 fps, or if the meter is not working, the
display will read as configured in the setup of the ‘Out of Range’ (i.e.
‘Hold’ (at last value), <4mA, 4mA or >20mA) and the ‘Overrange Rail’
parameters.
The ‘Out of Range‘ menu selection permits the user to specify the 4-
20mA output behavior when the meter cannot measure a valid flow
rate. The settings allow a less than 4mA output (‘<4mA’ actual output
of 3mA), a greater than 20mA output (‘>20mA’ actual output of
21mA), a constant 4mA output (‘4mA’), and a hold last valid reading
output (‘Hold’).
The ‘Overrange Rail’ selection is used to select the output behavior
when the flow velocity (and corresponding flow rate) goes below or
above the ‘Low End’ or ‘High End’ settings made earlier, but is still
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5.6
4-20mA Output vs. Flow Velocity
Flow Velocity (fps)
mA Out
p
ut