User Manual PROFview XL 4 The PROFview XL Application Software
4.7.3 Evaluation
During and after the measurement, this view displays the current, maximum and minimum measured values
of the disturbance-free voltage range with the appropriate time stamps. The slowest front and rear edges are
displayed in multiples of 1/16 of the bit width.
With the automatic evaluation activated ("Configure segment" view), the measuring instrument will indicate
the critical disturbance-free voltage range with a red arrow symbol. The relevant numerical value is displayed
in yellow, symbolizing that the smallest measured disturbance-free voltage range lies below the set limit val-
ue. If the critical edge value is exceeded, the edge diagram is displayed in yellow. If the value is below the
limit, the edge diagram is displayed in green.
It is possible to switch between the oscilloscope and the frame display both during and after the measure-
ment. The frame display displays the last detected frame. The oscilloscope displays a section of the signal
waveform for the measured station. Use the "Zoom" function ("+" and "-" buttons) to enlarge or reduce the
time section. To navigate within a zoomed-out section, use the scrollbar. Two cursors (1 and 2) which can be
positioned freely on the display can be used to measure reflections. To position the currently active cursor on
the oscilloscope display, press the left mouse button. To switch between cursor 1 and 2, click on the toggle
fields "1" or "2". The time difference between cursor 1 and 2 and the distance specification derived from the
signal propagation delay are also displayed.
4.8 "Quality Levels Logger" view
4.8.1 How to use
The logger measurement serves for a long-term analysis of the bus system up to several days. Thus, cyclic
impairments of the bus (external EMC interference) or a slowly worsening signal quality (e.g. by liquid pene-
trating into a connector) can be detected.
The quality levels of all stations highlighted in the station list as "to be measured" are measured once at defin-
able intervals. This provides an overview of the status of the signal quality over time for each station. A time
stamp that refers to the beginning of a logger interval is recorded for each measured value. The evaluation
function (if enabled) provides an overview of the whole measurement. It displays spots where the measured
values have not reached the setpoints and how many measurements could not be carried out ("not mea-
sured" or "Timeout"). Fig. 10 shows a screenshot of this view.
4.8.2 Setting and measuring
The requirements for this measurement are:
The PBT must be connected both to a PC and to the PROFIBUS plant (bus status LED = green/yellow)
The correct baud rate must be selected.
The master simulator must be activated if necessary (only required when performing a measurement on
an idle plant - bus status LED = yellow/red, differential voltage > 0.1 V)
The correct measuring point must be selected.
At least one station must exist in the station list and must be marked as "to be measured".
The required logger interval must be selected.
PROFview XL 25
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