Hart Sceintific DewK 1620, Руководство пользователя

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Be aware that automatic time changes due to the daylight saving time shift fea-
ture, and also manual time changes for that matter, will cause discontinuities in
the time that may have unusual effects that should be noted.
One possible effect is with recorded daily stats. If the record time is reached
twice within one day due to a time shift backwards, daily stats will be recorded
twice for the same date. This can happen if the daily stats record time is set to
00:00, the daylight saving mode is set to Europe, and a fall backwards time
shift occurs. Since the time 00:00 occurs twice for one day, two daily stats re-
cords will be created for the same day. It can also occur with the North Amer-
ica daylight saving mode if the daily stats record time is 01:00, since this time
will occur twice in one day.
Another effect is with viewing data on a graph in real time. Data is plotted on
the graph sequentially as measurements are made and the graph is scrolled uni-
formly. No adjustment is made to the real-time graph when the time changes.
However, when a graph is redrawn (using recorded data, as a result of changing
the display layout or cycling the power) in preparation to resume real-time plot-
ting, the thermo-hygrometer attempts to accurately plot measurement points at
the appropriate time locations. Thus, a one-hour spring daylight saving time
shift will appear as a one-hour gap in the data on the graph. When a jump back-
wards is found in the recorded data, such as occurs during the fall daylight sav-
ing time shift, the thermo-hygrometer makes no attempt to plot the data prior to
the time shift; there will appear to be missing data on the left side of the graph.
Graphs drawn using the DATA VIEW function behave similarly when time dis-
continuities occur in recorded data. A one-hour jump forward in time causes a
one-hour gap in the data on the graph. However, a one-hour jump backwards in
time produces a graph that also includes the data prior to the time shift. The re-
peated hour of data is also plotted but is compressed into one time point, the
time just prior to the time shift. In other words, the data prior to the time shift is
plotted first. Then when data for the first hour after the one-hour shift back-
wards is encountered, the data is plotted as if it all occurred at the instant of the
time change. Then when the hour's data has passed, plotting resumes normally
and the data is plotted to the right of the time shift.
Note that in any case data is recorded to memory as would be expected, with a
one hour time gap or a repeated hour when a daylight saving time shift occurs.
The effects of the automatic daylight saving time shifts should cause minimal
inconvenience, as they occur early Sunday morning. To prevent confusion and
time ambiguity problems, avoid running environment-sensitive operations dur-
ing the daylight saving time shift. Also consider temporarily suspending data
recording for days on which daylight saving time shifts occur. But if you do
this, be sure to resume data recording when you need it!
The
ud
buttons are used to select the menu parameter. The
lr
buttons are
used to change the parameters. Press the Enter button to save the new setting.
Press the Exit button to cancel any changes and exit to the menu.
68 Hart Scientific
7 Menu Functions