Dynasonics TFXM Series Ultrasonic Multi-Channel Flow Meter - Manual (Page 76)

Rev. 8/02 -4. 9- TFXM
Example:
If the average flow rate is 100 GPM and the Flow Filter
Hysteresis is set to 5%, a filter window of 95-105 GPM is
established. Successive flow measurements that are
measured within that window are recorded and averaged in
accordance with the Flow Filter Damping setting. Flow
readings outside of the window are held up in accordance
with the Bad Data Rejection Filter.
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Flow Filter MinHysteresis sets a minimum hysteresis window
that is invoked at low flow rates, where the “of rate” Flow
Filter Hysteresis is very small and ineffective. This entry is
entered in pico-seconds and is differential time. This value is
factory set and should not be altered without consulting the
Dynasonics technical services department.
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Flow Filter Sensitivity allows configuration of how fast the
Flow Filter Damping will adapt in the positive direction.
Increasing this value allows greater damping to occur faster
than lower values. Adaptation in the negative direction is not
user adjustable.
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Bad Data Rejection is a value related to the number of
successive readings that must be measured outside of the
Flow Filter Hysteresis and Flow Filter MinHysteresis
windows before the flow meter will use that flow value. Larger
values are entered into the Bad Data Rejection when
measuring liquids that contain gas bubbles, as the gas
bubbles tend to disturb the ultrasonic signals and cause more
extraneous flow readings to occur. Larger Bad Data Rejection
values tend to make the flow meter more sluggish to rapid
changes in actual flow rate.
SOFTWARE UTILITIES