Hydrological Services Pty Ltd
Data Logger Model ML1-420
©
Copyright
ML1-420 100-29
Issue 1.00 6 Apr, 2011
5.8 System
Memory
A fundamental requirement of the logger unit is for sufficient memory capacity to store
400,000 events.
In most cases the MiniLog can be returned to the processing centre via surface mail. The
logger’s small size and weight means the package returned, conforms with low cost postage
tariffs.
The logger application requires three essential memory areas,
Data Memory
for storage of
the historical records,
Program Memory
for storage of the application firmware and
Paramter Memory
to store unique station parameters.
5.9 System
Clock
The clock performance in terms of reliability and maintainable accuracy is of prime
importance as the historical record is unusable should time and date errors occur. The clock
should maintain an accuracy of better than 20 seconds per month with resolution to one
second across an operating temperature range from –10
o
C to +70
o
C. The Time Adjust
command allows for automatic software adjustment of the real time clock crystal.
5.10 Logger Identification
Each logger has a six digit unique identification number hard coded and accessible as a
read
only system parameter via software.