MBW 473-RP2 Operation And Maintenance Manual Download

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MBW 473 Manual English V5.0

Fixed Range

The Fixed Range mode allows you to select a fixed range

for the graph’s y-axis. It automatically cen-

ters on the most recent data point. As the most recent data varies, so will the center point of the graph,
leaving the overall range fixed. The Fixed Range mode is mostly used to monitor data for stability. For
example, if you set the fixed range for the external temperature graph to 0.2 and the current data is
23.00 °C all data between 22.80 °C and 23.20 °C is visible on the graph.

Minimum/Maximum

In  the  Minimum/Maximum  mode  you  can  specify  the  minimum  and  maximum  values  used  for  the
graph’s  y-axis.  Unlike  the  other  modes,  the  visible  range  of  the  graph’s  y-axis  will  not  automatically
change  if a data point is outside the set minimum/maximum range. If the data points are  outside the
specified range, you will not see them on the graph.

Time Span

Time Span determines the number of minutes of the data history that is visible on the graph. The 473
stores a fixed number of data points independent of the selected time span. Thus, changing the time
span will change the time interval at which the data points are stored. The total number of stored data
points will not change. With a time span of 15 (15 minutes), the graph data is sampled and stored
every few seconds. With a time span of 120 (2 hours), the graph data is only sampled, stored, and
updated about once a minute.

When you change the time span, the data that was sampled and stored at the old interval will be in-
crementally replaced by new data sampled at the new interval. The time span indicated on the graph
will always reflect the actual time span of the data that is displayed on the graph, and will agree with
the time span you selected once enough data points have been sampled. The selected time span is
common to all graphs, so they will always have the same time relationship to one another.

The time span can be changed in the Numeric/Graphic menu:

1. Touch the graph you wish to change on the screen. The Graph Scaling dialog box will appear.

2. Touch the

Change To:

field next to

Time Span

. The field will turn white.

3. Use the numerical keypad to enter an

even

value between 2 and 1440. As you enter the value it

will appear in the white

Change To:

field of the dialog box.

4. If you make an entry error, touch the field that holds the number you wish to change. Each time

you touch the field, the last digit entered will be deleted.

5. Press the OK button in the dialog box or press Enter on the key board to confirm the new value.

Press Cancel to leave it unchanged.

6. The result will take some time to show as the old data at the old time interval will be replaced by

data at the new time interval gradually as determined by your selected time span.

If you prefer to see the same measurement as both numerical value and graph, you may
select the same parameter on two data lines, and set one line to graph mode and the
other to numeric mode. See sections 5.2 and 5.3 for instructions on selecting displayed
parameters and changing their display modes.