LogTag Recorders LogTag Analyzer Temperature Recorder Benutzerhandbuch

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Chapter 5    Results from LogTag 
65 
 
 
Degree Minutes 
There are some products and materials that exist which can change their characteristics 
and/or degrade if they experience temperatures which are not within ideal conditions for 
long enough. For example, some products may experience freezer burn if they experience 
an extremely cold condition or experience a colder than ideal temperature for long 
enough period of time. Other products for example, ice cream, change their 
characteristics if they experience temperatures which allow it to melt. The LogTag 
Analyzer will automatically display the results of two separate Degree Minutes 
calculations. The result of the first Degree Minutes calculation displayed will be based on 
the readings that were recorded below the ideal conditions and the result of the second 
Degree Minutes calculation displayed will be based on the readings that were recorded 
above the ideal conditions. The ideal conditions used in the calculation of the Degree 
Minutes formula are based on the upper and lower alert values that where configured 
when the LogTag was originally prepared for use. 
 
Mathematically the formula for calculating the degree minutes above alert can be 
expressed as illustrated in the following picture: 
 
Where: 
degmin 
Total Degree Minutes spent above/below the alert 
threshold. 
t
i
The temperature that was above/below the alert threshold. 
The alert temperature threshold. 
The duration of time, in minutes, the temperature was 
sustained. 
For example, if there were 5 data points to calculate the degree minutes of and they 
were, 12.3, 15.9, 16.2, 14.7 and 14.9 degrees, each of these temperatures were recorded 
at 2 minute intervals and the high alert temperature threshold was 12.6 degrees, then the 
degree minutes temperature above the upper alert threshold would be 22.6 degree-
minutes.