Larson Davis 831, User Manual

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Model 831 Manual Timed Stop Mode 12-3
Valid Measurement Times
When other values are selected, the
interval time sync will still function,
but the time for which the first
measurement is cut short will be
different. See "Other Measurement
Times" below for further detail. The interval time sync function is intended to be used with
the following measurement time values:
• 1, 5, 10, 20 or 30 minutes
• 1 hour
When the interval time sync function is used, each hour is
divided into a number of equal time segments, based on the
number of time intervals contained within one hour. For
example, when the time interval is five minutes, there will
be twelve segments within any one hour period beginning at
xx:00:00, xx:05:00, xx:10:00, etc.
The instrument will begin the first measurement when the
9
(RUN/PAUSE) key is pressed. Regardless of the start
time, when the clock of each instrument reaches the time
corresponding to the beginning of the next segment, the
measurement in progress will be stopped and stored, and a
new measurement will be started.
Other Measurement Times
When values of measurement other than those listed above
are used, the clock time at which the first measurement is cut
short is based solely on the units of the measurement time;
seconds, minutes or hours. For example, suppose the
measurement time is set to three minutes. Based on the unit
of minutes, the time intervals per hour are xx:00:00,
xx:01:00, xx:02:00, etc. If the measurement were begun at
08:14:23, the first measurement would be cut short at the
next measurement interval, so subsequent measurements
would be started at 08:15:00, 08:18:00, 08:21:00, etc.
Timed Stop Mode
The Time Stop Mode with Measurement History has a
feature not included for the other run modes; the ability to
automatically measure and store a user-defined number of
records, then stop. Subsequent runs, each manually initiated,
will produce the same number of stored measurements.