Parameter Description - Siemens SIMATIC ET 200S Manual

Parameters

2.2 Parameter description

Temperature coefficient
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 temperature coefficient depends on the chemical composition of the material. Only one
value is used in Europe for each type of sensor (default value).
Additional values enable you to make a sensor-specific setting for the temperature
coefficient, therefore ensuring more accuracy.
2.2 Parameter description
Smoothing
The individual measured values are smoothed by digital filtering. The smoothing can be
adjusted in four steps, in which the smoothing factor k multiplied with cycle time of the
electronic module equals the time constant of the smoothing filter. The higher the smoothing
the greater the time constant of the filter.
The following diagrams show the step response with the various smoothing factors
depending on the number of subassembly cycles.
Figure 2-1
20
Smoothing with 2AI RTD HF
2AI RTD HF analog electronic module (6ES7134-4NB51-0AB0)
Manual, 05/2007, A5E01076876-02