Arroyo Instruments TECSource 5305, Руководство пользователя

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Page 26 · 5300 Series TECSource User’s Manual
User Calibration of Resistance Sensors
In some applications, having the ability to compensate, or calibrate, the sensor
measurement is desired, such as referencing to an internal standard or to match
the readings of another instrument. This is supported on the TECSource by
using the Sens Cal M and Sens Cal B menu entries to apply an offset and/or
slope compensation to thermistor or RTD readings (LM335 and AD590 sensors
have separate M and B settings).
To prevent accidental modification of the sensor calibration, the
Sens Cal M and
Sens Cal B menu entries are only editable when the Edit User Cal setting in the
System sub-menu is set to Yes . By default, Sens Cal M and Sens Cal B values
are 1.000 and 0.00, respectively, but can be adjusted to change the sensor
measurement. The calibrated measurement is computed as follows:
User calibrated reading = Sens Cal M * r Sens Cal B
Sens Cal B is displayed in kilo-ohms (k Ω ) for thermistors, and ohms (k Ω ) for
RTDs.
Be aware that the there is only a single set of calibration values, and changing
sensor type does not change the calibration data. Therefore, if you will be
changing between thermistor to RTD sensors, you will need to change the
calibration values as appropriate for the new sensor setting. Changing the
values back to 1.000 and 0.00 will return the instrument to factory calibration.
NOTE
The calibration is applied to the resistance measurement
of the sensor, not the temperature. To adjust the
resistance-to-temperature conversion, change the
thermistor or RTD coefficients as needed.