INTRODUCTION

Kooltrak Professional includes a feature that can apply a correction to temperature data read from a logger in accordance with a correction table held in a calibration file. This calibration file can be created manually by the system user, or can be supplied by Kooltrak Inc. when logger calibration is purchased.

When a logger is "read" a two step process takes place. First the data from the logger is written into a file with a file name including the logger ID number and the date and time with extension ".dta", and then that .dta file is processed into the database.

If the logger is read directly into the PC on which Kooltrak is installed these steps are performed automatically and invisibly. Otherwise, if the logger is read using for example a hand-held computer (ie a PocketPC) then the logger data is written to the .dta file by the PocketPC, and at a later time the .dta file is processed into the PC database by Kooltrak running on the PC. In both cases a copy of the un-modified data in the .dta file is saved in the ..\Kooltrak\data\backup directory.

The calibration file correction is applied when the .dta file is processed into the database.

The Kooltrak system allows .dta files to be re-processed as a way of rebuilding the database, and at that time they will again be corrected using the current calibration file. The emphasis on current is because it could be that at an earlier time an earlier version of the calibration file applied, and this would be the case if for example a logger was recalibrated annually. Managing the application of the correct calibration file must be done manually, and there is a field in the file containing the file creation date to assist in this process.

As a further safety check the correction and reprocessing will not be performed and an error will be returned if data for the same date and time already exists in the database for the logger being reprocessed..

SYSTEM REQUIREMENTS

In order for data correction to be performed by Kooltrak Professional a file named [ID#].dtc containing correctly formatted information must exist in the directory ..\Kooltrak\data\calibration\ where [ID#] matches the ID# of the logger being read or the .dta file being reprocessed.

CALIBRATION FILE FORMAT

The calibration file is a text file with a file name of [ID#].dtc and contents as follows. Lines are seperated by CR/LF. Information after the "\" character is a comment that is not part of the calibration file.

Note that these parameters apply to Kooltrak logger types 211002, 212004, 213004, 214002 and 217001. The "logger minimum reading in Celsius" parameter is -40C for all these loggers even though they may not be rated to operate down to this temperature. All these loggers use a temperature representation with 256 possible values (8 binary bits) where the lowest possible value corresponds to -40C.

Other parameters apply to logger types 212101, 212201, 213101 and 213201.

The resulting value after correction should not fall outside the range -40C to +85C. It may be necessary to trim the correction values at the ends of the range to satisfy this requirement.

CALIBRATION FILE EXAMPLE

The following example calibration file was generated for a logger with ID# 1813389008 and the following characteristics.

 

File name: 1813389008.dtc

V1
comment
1813389008
2003-05-12
-40
255
0.5
0.00
-0.01
-0.02
-0.04
-0.05
-0.06
-0.07
-0.09
-0.10
-0.11
-0.12
-0.13
-0.15
-0.16
-0.17
-0.18
-0.20
-0.21
-0.22
-0.23
-0.24
-0.26
-0.27
-0.28
-0.29
-0.30
-0.32
-0.33
-0.34
-0.35
-0.37
-0.38
-0.39
-0.40
-0.41
-0.43
-0.44
-0.45
-0.46
-0.48
-0.49
-0.50
-0.51
-0.52
-0.54
-0.55
-0.56
-0.57
-0.59
-0.60
-0.61
-0.62
-0.63
-0.65
-0.66
-0.67
-0.68
-0.70
-0.71
-0.72
-0.73
-0.74
-0.76
-0.77
-0.78
-0.79
-0.80
-0.82
-0.83
-0.84
-0.85
-0.87
-0.88
-0.89
-0.90
-0.91
-0.93
-0.94
-0.95
-0.96
-0.98
-0.99
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-1.00
-0.98
-0.97
-0.95
-0.93
-0.91
-0.90
-0.88
-0.86
-0.84
-0.83
-0.81
-0.79
-0.78
-0.76
-0.74
-0.72
-0.71
-0.69
-0.67
-0.66
-0.64
-0.62
-0.60
-0.59
-0.57
-0.55
-0.53
-0.52
-0.50
-0.48
-0.47
-0.45
-0.43
-0.41
-0.40
-0.38
-0.36
-0.34
-0.33
-0.31
-0.29
-0.28
-0.26
-0.24
-0.22
-0.21
-0.19
-0.17
-0.16
-0.14
-0.12
-0.10
-0.09
-0.07
-0.05
-0.03
-0.02
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00

end.