Danfoss AK2-SC 255 Reference Manual page 191

Rate
Scroll
Mode: Latest
or Snapshot
Graph
190
The five selected datapoints are listed at the top of the screen. Next, the start date
and time for the display are shown. You can change the start date and time as you
would any other numeric field.
The last line in the screen heading contains the display interval and the scroll setting.
The Rate determines the interval between displayed lines of data in the body of the
screen. It is important to remember that the display rate is not necessarily the sample
rate, which is set during history configuration (see Chapter 4-9). Often the display
rate and the sample rate may not be the same. If not, the displayed value for a given
datapoint will be the most recent as of the display rate time.
The Scroll field regulates how much of the screen will be scrolled when you press
one of the small arrow buttons in center bottom of the screen. The selections possible
are Full (for full screen scroll), Half, one sample, or any of 9 time periods ranging
from 2 minutes to 1 day.
There are two modes, Latest and Snapshot, in which history data can be displayed,
applying to both the columnar display as seen in the example above and to graphing.
In Latest mode, the display shows the most recent history, ending with the value of
the most recent sample; the display is updated as each new sample is recorded,
constantly moving forward. In Snapshot mode, you can display any stored history
for the selected points, from the oldest data to the present.
The Graph button will present a graph of the displayed data. If the display is in
Latest mode, the graph will plot as each new sample is collected. A typical graph
screen looks like this one::
AK2-SC 255 Reference Manual RS.8D.M1.22