Siemens SIMATIC ET 200AL, Системное руководство

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Parameters/address space
4.3 Explanation of the parameters
Analog input module AI 4xRTD/TC 4xM12 (6ES7144-5KD50-0BA0)
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Equipment Manual, 08/2021, A5E48753535-AB
"Fixed reference temperature" parameter for thermocouples
The parameter "Fixed reference temperature" can only be set if you selected = "Fixed
Reference Temperature" for the "Reference junction" parameter.
The following table shows the value ranges for the "reference temperature" for
thermocouples.
Table 4- 4 Value ranges for the "reference temperature" for thermocouples.
Temperature unit Temperature Decimal
Min. Max Min. Max
Celsius -145.0 155 -1450 1550
Fahrenheit -229.0 311.0 -2290 3110
Kelvin 128.2 327.6 1282 3276
4.3 Explanation of the parameters
Temperature unit
You use this parameter to set the temperature unit with which you want to measure the
temperature.
Type/range of measurement
You use this parameter to set the measurement type or the measuring range for acquiring
the measured values.
Note
Unused channels
"Deactivate" unused channels in the parameter assignment to improve the cycle time of the
module.
A deactivated channel always returns the value 7FFF
H
.
Temperature coefficient (for RTD)
The temperature coefficient depends on the chemical composition of the material. In Europe,
only one value is used per sensor type (default value).
The correction factor for the temperature coefficient (
α value) specifies how much the
resistance of a certain material changes when the temperature is raised by 1 °C.
The further values facilitate sensor-specific setting of the temperature coefficient and
enhance accuracy.