Siemens SITRANS FUH1010PVX, Руководство по эксплуатации, Страница: 98 / 226

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1010BXFM-3 Section 2
2.5.1 MEMORY/FAULT SET
Certain situations (e.g., an empty pipe or excessive aeration) will interrupt data production.
Use [Memory/Fault Set] to select the meter response to such an interruption. The Fault set-
ting (default) will zero the output and declare an alarm on the display screen, Datalogger
report and an assigned relay output.
For some applications, however, occasional temporary Fault conditions may be a normal part
of the process and would not require an alarm response. The system offers a Memory operat-
ing mode to support such an application.
Memory Mode suspends the system’s Fault response by preventing the outputs from dropping
to zero for the interval specified in the Memory Delay menu cell. During the Memory dura-
tion, the meter will maintain the last valid reading measured before the onset of the fault
condition. The default Memory Delay is 60 seconds. You may select any duration from 3 to
604,800 seconds (one week).
To select Memory mode:
To access the [Memory/Fault Set] option list press
Move the cursor down to [Memory] by pressing
To make selection press
This moves the highlight to the [Memory Delay (sec)] menu cell.
2.5.2 MEMORY DELAY (sec)
Selecting [Memory] activates the suppressed [Memory Delay] menu cell. It allows you to specify
the number of seconds that the meter maintains its last valid reading. When the memory
delay expires, it triggers the fault alarm response described previously.
To specify the Memory delay:
To enable numeric entry press
Use PC numeric keys or Magnetic Wand to type the delay in seconds.
To register the new value press
2.5.3 SONILOCATOR OPERATION
NOTE: Sonilocator functions are only active when the flowmeter is used in conjunction
with Controlotron’s Leak Detection/Location software.
In the event of a pipeline leak, a sudden drop in pressure occurs radiating a pressure wave
both upstream and downstream from that point at the speed of sound in the liquid. This drop
in pressure decreases the density of the liquid, which results in a sudden drop in the current
value of the liquid’s sonic propagation velocity (Vs). Vs is measured at each of the upstream
and downstream Site Stations (metering points) an average of ten times per second. The
decrease in Vs is detected and time stamped with the arrival of the pressure wave’s leading
edge. Since both Site Stations have synchronized time clocks, the relative arrival times of the
pressure waves at each Site Station is easily determined. The accuracy of the location function
is dependent on the resolution of time stamping and the sonic propagation velocity of 1500
meters per second.
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