Nautilus Data Loggers
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1.4
APPENDIX A Nautilus 85/135 Sample Rates
Nautilus 85/135 Sample Rates
1.4.1
How a Data Logger Stores Readings
The sample rate of your data logger is the frequency with which it stores readings in its
memory. A selected sample rate applies to the channel on a Nautilus.
If you set your data logger's sample rate to eight seconds, it reads its input channels and
stores the readings once every eight seconds. If you choose a sample rate longer than eight
seconds, the logger still reads its input channels once every eight seconds, and stores an
averaged reading at the end of the sample interval you have chosen if the sampling mode is
set to Average.
For example, if you use a two-minute sample rate, the data logger takes fifteen separate
readings over each two-minute interval. At the end of each two-minute interval, the logger
calculates the average of the fifteen readings, and stores that average in its memory.
Otherwise if the sampling mode is set to Spot the logger still takes readings every 8 seconds
but only stores the reading taken at the selected interval.
1.4.2
Sample Rate Tables
The following tables list the maximum time spans over which your Nautilus will record
readings. The time spans depend on the length of the sample rate. A Nautilus has a memory
capacity of up to 32,640 readings when data compression not selected and up to 244,800
readings when data compression is selected.
In each table, the Sample Rate column lists the available sample rates. The Days, Hours,
Minutes and Seconds columns list the time spans over which your logger will record readings
at each sample rate.
For example, a 32KB Nautilus with 5 times compression (4-5 times is typical) and using a
sample rate of ten minutes will store readings for 3 years, 38 days and 8 hours. After that
time, depending on how it was set up, the logger will either continue to take readings and
replace the oldest readings with the new readings (FIFO), or it will stop taking readings (Stop
When Full).
Table B-1: 32KB Nautilus 85/135 Sample Rate Table with Compression (max)
Sample Rate
Years
Days
Hours
Minutes
Seconds
8 sec.
0
22
16
0
0