Siemens SITRANS FUP1010, Руководство по эксплуатации, Страница: 123 / 208

Diagnostic Text Display
The text to the upper left-hand corner of the screen represents diagnostic items which can be
individually turned on or off to reduce unnecessary clutter on the screen. This text display can
be modified by pressing the <ENT> key and scrolling up or down through the various
parameters that appear in the Graph Display menu. Pressing the <ENT> key will select the
highlighted parameter (a "+" sign appears next to selected items) and pressing <CLR> will
deselect the item. Pressing the <Left Arrow> will return you to the graph screen with the
selected parameters appearing at the top left corner of the screen. (The sample graph above
is shown with all diagnostics items selected).
Time Base Control
The digitized receive signal can be moved either to the left or right on the screen by pressing
the <Left> or <Right> keypad arrows. The direction of the arrow actually represents the
direction in which the Receive "window" will move, thereby causing the receive signal to shift
in the opposite direction on the screen (e.g., Pressing the <Left Arrow> moves the signal to
the right).
The digitized receive signal can be expanded or contracted in the time domain by pressing the
<+> or <-> keys on the keypad. This allows you to see the entire contents of the receive window,
or zoom in to see greater detail. Pressing the <CLR> key once will automatically center the
receive signal on the screen. When expanding the receive signal small vertical "tick" marks
will eventually appear. These marks represent the time at which the receive signal is digitally
sampled.
Correlated Plot
During conditions of flow, the actual transit time delta (difference) can be observed in the
displayed receive signal waveform when the [Correlated Plot] menu parameter is not selected.
To observe this time difference simply depress the <+> key (to see greater signal detail) until
the individual up and down receive signals are clearly discernible. To verify that the flowmeter
signal processing algorithms are properly correlating the up and down stream receive signals,
select the [Correlated Plot] option from the display menu list.
Return to the graph screen and observe the relative position of the up and down waveforms.
In a properly correlated receive signal the two images should be nearly superimposed on top
of each other, even during high flow conditions. In the unlikely situation where the two images
appear to be offset by one or more receive cycles then the flow readings should be considered
questionable.
Command Modes
Although the flowmeter signal processing algorithms are capable of accommodating a very
wide range of signal conditions, it may be desirable to override these default settings under
extremely difficult operating conditions. The following functions are available for this purpose.
Digital Damping Control: (Hot Key 1 and 2)
The meter permits user modification of the digital averaging used by the signal processing
routines. In general, the default damping values selected by the flowmeter will provide optimal
performance over a wide range of transit time applications. However, in extreme cases of
Troubleshooting
10.3 Test Facilities Graph Screen
FUP1010 IP67 Portable Flowmeter
Operating Instructions, 02/2010, A5E02951522A Revision 01 121