Campbell Scientific for more information. Strapping the transducer body with tie wraps or tape
will not hurt it.
6.6 Battery voltage reading
The voltage of the lithium ion battery used in the CRS451/CRS456 will abruptly decrease at the
end of the battery’s useful life, which makes predicting remaining battery life difficult by
measuring battery voltage alone. Knowing the energy consumption of the CRS451/CRS456 while
in operation, HydroSci displays a predicted remaining battery life by combining an estimate of
the energy consumed based on the totalized measurements since new and direct battery
measurements. For this reason, if the battery is removed from the CRS451/CRS456 anytime
during deployment and then replaced, HydroSci will assume a fresh battery was added to the
device and the estimated remaining battery life will be overstated.
For similar reasons, if the operating system is upgraded or sent to the CRS451/CRS456, the
estimated remaining battery life will also be exaggerated by HydroSci.
6.7 Memory
The internal data memory stores 4,000,000 bytes of data. Each table record uses 4 bytes for a time
stamp and 4 bytes for each data value. For example, a table with two data values, such as
pressure and temperature, will use 12 bytes per record. If a record is written every 30 seconds, the
number of records that occur each day is:
Records per day = 86,400 s / 30 s = 2880 records
Therefore, the memory used in one day is:
Bytes per day = 2880 x 12 bytes = 34,560
Therefore, the memory will last:
Number of days = 4,000,000 bytes / (34,560 bytes/day) = 115 days
CRS451/CRS456 Submersible Water-Level Recording Sensor
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