H49.0.02.6C-02
Operating Manual MH 3750
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4 Special Functions
4.1 Display Resolution
Standard setting: 'Auto', i.e. the device automatically switches over to the optimum resolution between .01° and 0.01°.
If temperatures to be measured are near the switching threshold, a fixed resolution may be better, e.g. for easy
recording. In such a case please select the optimum resolution manually.
4.2 User Sensor Curve ('Lin USEr')
By means of this function besides the standard conversion of resistance to temperature following EN60751(Lin E.751)
also other curves can be used. The user sensor curve can be read and edited by the configuration software
MHKONFIG. The standard setting ex works is also set to the EN60751 data. The curve is defined by a table with two
columns (input resistance[Ohm]/output temperature [°C]) with 50 rows.
Info: The sensor curve following EN60751 uses the international temperature scale ITS90 and following formulas:
Temperatures <0°C:
Temperatures >=0°C:
4.3 Zero Displacement ('Offset')
A zero displacement can be carried out for the measured temperature:
temperature displayed = temperature measured - offset
Standard setting: 'off' = 0.0°, i.e. no zero displacement will be carried out. Together with the scale correction (see
below) this factor is mainly used to compensate for sensor deviations. Unless the factor is set to 'off', the offset arrow in
the display shows an active zero displacement.
4.4 Scale Correction ('Scale')
The scale of the measuring can be influenced by this setting (factor is in %):
displayed temperature[°C] = measured temperature[°C] * (1+Scal/100)
respectively displayed temperature[°F] = (measured temperature [°F]-32°F) * (1+Scal/100) + 32°F
Standard setting: 'off' =0.000, i.e. temperature is nor corrected. Together with the zero displacement (see above) this
factor is mainly used to compensate for sensor deviations.
Unless the factor is set to 'off', the Corr arrow in the display shows an active scale correction.
4.5 Output
The output can be used as serial interface (for GRS3100 or GRS3105 interface adapters) or as analogue output (0-
1V). If none of both is needed, we suggest to switch the output off, because battery life then is extended.
4.5.1 Interface - Base Address ('Adr.')
By using an electrically isolated interface converter GRS3100 or GRS3105 (accessory) the device can be connected to
a PC. With the GRS3105 it is possible to connect up to 5 instruments to a single interface (please also refer to
GRS3105-manual). As a precondition the base addresses of all devices must not be identical. In case several devices
will be connected via one interface make sure to configure the base addresses accordingly. In order to avoid
transmission errors, there are several security checks implemented (e.g. CRC).
The following standard software packages are available for data transfer:
§
EBS9M
:
9-channel software to record and display the measuring values
§
EASYControl
:
Universal multi-channel software (EASYBUS-, RS485-, and/or MH3000- operation possible) for
real-time recording and presentation of measuring data in the ACCESS®-data base format.
In case you want to develop your own software we offer a
MH3000-development package
including
-
an universally applicable 32bit Windows functions library ('MH3000.DLL') with documentation that can be used by
all 'serious' programming languages.
-
Programming examples for Visual Basic 6.0™, Delphi 1.0™, Testpoint™, Labview™
Note:
The measuring and range values read via interface are always in the selected
display unit (°C/°F)!
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SIKA, Dr. Siebert & Kühn GmbH & Co. KG, Struthweg 7-9, 34260 Kaufungen, Germany
Tel: +49-5605-803-0, Fax: +49-5605-803-54, email: [email protected], web: www.SIKA.net
