dynasonics TFXL, Инструкция по установке и эксплуатации

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MAX Flow is used by the TFXL to establish filter settings in
its operating system. Enter a flow rate that is the
maximum, positive flow rate anticipated within the system.
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The Damping value is increased to intensify stability of the
flow rate readings. Damping values are decreased to allow
the flow meter to react faster to changing flow rates.
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Low Flow Cutoff is entered as a percentage between MAX
Flow and MIN Flow and influences how the flow meter will
act at flows very near zero. Generally, an entry of 1%
provides for a stable zero indication, while providing a
100:1 turndown ratio for measurements.
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Low Signal Cutoff is a relative value that should be
entered after a successful flow meter startup. For an initial
value, enter 5% [Signal Strength indications below 3% are
considered to be below the noise ceiling and should not be
indicative of a successful flow meter startup.] The entry has
three purposes: provides an error indication—Low Signal
Strength [Error 0010 on the TFXL display] when liquid
conditions in the pipe have changed to the point where flow
measurements may not be possible, warns if the pipe’s
liquid level has fallen below the level of the transducers,
and signals that something with the flow meter installation
or configuration may have changed. Examples would
include such things as the couplant used to mount the
transducer has become compromised, a cable has become
disconnected or a pipe size setting has been altered.
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Substitute Flow is used to provide an indication and output
that signifies that an error exists with the flow meter or its
setup. It is set as a percentage between MIN Flow and
MAX Flow. In a uni-directional system this value is typically
set to zero, to indicate zero flow while in an error condition.
In a bi-directional system, the percentage can be set such
that zero is displayed in a error condition. To calculate out
where to set the Substitute Flow value in a bi-directional
system perform the following operation:
Substitute Flow = 100 x MAX Flow ____
MAX Flow + MIN Flow