eDAQ Quad Tc/mV, Руководство пользователя

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12 Quad pH/mV Amp
Units Calibration
Clicking the button access the Units Conversion dialog box.
For more information about Units Conversion, see the Chart Software
Manual . This type of calibration should only be used for small
temperature ranges that can be calibrated with only two accurately
known temperature sources.
See the next section for calibration of probes, without the need of
accurately known temperature sources.
When calibration is required over a wide range of temperature and
several accurately known temperature sources are to be employed then
use the Multiple Point Calibration extension.
Calibration
Automatic Calibration
The Thermocouple extension is a Chart software plug-in that adds the
‘Thermocouple...’ command to the Chart channel pop-up menus. The
latest version of the extension is available at
http://www.edaq.com/chart_extns_list.html
This extension:
• allows the user to select the type of thermocouple (B, E, J, N, K, R,
S or T) being used;
• applies a polynomial correction to convert the voltage signal to
degrees (°C, °F, or K) according to the thermocouple ITS-90 tables,
see http://srdata.nist.gov/its90/main/
The resulting temperature values will usually be accurate within the
tolerance of the thermocouple being used — consult your thermocouple
probe documentation. In most cases thermocouples conform to either
the ANST/ANSI E230 Standard, or Special, Limits of Error, see
Table 2–2 . In some cases, especially over limited temperature ranges,
manufacturers may guarantee better tolerances.