Siemens SITRANS LR200 7ML5422, Руководство по эксплуатации

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SITRANS LR200 with mA/HART
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Operating Instructions, 05/2019, A5E32337676-AE
Once the real process fill/empty rate (m/s by default) is established, a response rate can be
selected that is slightly higher than the application rate. Response Rate automatically adjusts
the filters that affect the output response rate.
Response Rate (2.4.1.) Fill Rate per Minute (2.4.2.)/Empty Rate per
Minute (2.4.3.)
Damping Filter (2.2.4.)
* Slow 0.1 m/min (0.32 ft/min) 10 s
Medium 1.0 m/min (3.28 ft.min) 10 s
Fast 10.0 m/min (32.8 ft/min) 0 s
B.2.9 Damping
Damping filter (2.2.4.) (Page 100) smooths out the response to a sudden change in level.
This is an exponential filter and the engineering unit is always in seconds.
In 5 time constants the output rises exponentially: from 63.2% of the change in the first time
constant, to almost 100% of the change by the end of the 5th time constant.
Damping example
time constant = 2 seconds input (level)
change = 2 m
B.3 Analog output
The mA Output (current output) is proportional to material level in the range 4 to 20 mA. 0%
and 100% are percentages of the full-scale reading (m, cm, mm, ft, in). Typically mA output
is set so that 4 mA equals 0% and 20 mA equals 100%.
When SITRANS LR200 is put into PROGRAM mode (for example, by navigating through the
menu) it stops updating the output of the device (local user interface and mA Output). It
stores the most recent measurement, and holds the associated readings and mA signal
output. The device reverts to the parameter last addressed during the previous program
session.
When the device is returned to Measurement mode, the transceiver resumes operation. The
reading and mA output default to the last measurement taken. The reading and associated
outputs migrate to the current process level at a rate controlled by Response Rate (2.4.1.)
(Page 101).
If the device is left in PROGRAM mode for 10 minutes without input, it automatically reverts
to Measurement mode.
Two parameters affect the mA output: Operating Mode and Current Output Function.