Siemens sitrans tr300, Руководство пользователя

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Functions
9.13 Sensor calibration
SITRANS TR200/TR300
Operating Instructions, 06/2010, A5E01071992-03
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9.13 Sensor calibration
9.13.1 Sensor calibration (one point)
This function allows the characteristic curve of the sensor that is connected to be shifted to
intersect the zero point. This allows calibration of the start of scale value of the input sensor.
This does not affect the measuring span.
Entering a one point trim is equivalent to entering a sensor offset. The result of the one-point
trim is saved in the "offset sensor" variables.
9.13.2 Sensor calibration (two point)
This function allows the characteristic curve of the sensor that is connected to be shifted to
intersect two calibration points. The results are then correct measured values at the sensor
trim points. A two point trim makes it possible to reduce the proportion of errors due to the
characteristic curve.
Trimming the lower sensor calibration point
With these function:
● Apply the process variable on which the lower sensor calibration should be performed is
applied, e.g. temperature or resistance, to the transmitter input.
● Use the operating software to command the transmitter to load this process value.
SITRANS TR200 uses SIPROM T operating software, SITRANS TR300 uses
SIMATIC PDM operating software or the HART communicator.
Loading the process value represents an offset shift of the characteristic curve, see B, in the
"Sensor calibration" diagram.
Trimming the upper sensor calibration point
With these function:
● Apply the process variable on which the upper sensor calibration should be performed is
applied, e.g. temperature or resistance, to the transmitter input.
● Use the operating software to command the transmitter to load this process value.
Loading the process value represents a slope correction of the characteristic curve, see C, in
the "Sensor calibration" diagram. The lower sensor trim point is not affected by this.