Siemens SIMATIC ET 200S - Smoothing

Analog Electronic Modules
12-39
ET 200S Distributed I/O System
EWA-4NEB 780602402-12
Smoothing
The individual measured values are smoothed by means of digital filters. The
smoothing can be configured in four levels, in which the smoothing factor multiplied
by the cycle time of the electronic module corresponds to the time constant of the
smoothing filter. The greater the smoothing the greater the time constant of the
filter.
The following diagrams show the jump response with the various smoothing
factors depending on the number of module cycles.
• Smoothing with 2AI U Standard, 2AI U High Feature, 2AI I 2WIRE Standard,
2AI I 4WIRE Standard, 2AI I 2/4WIRE High Feature, 2AI RTD Standard,
2AI RTD High Feature, 2AI TC Standard, 2AI TC High Feature
0.5
1
0
0.63
50
100 150
Module cycles
None: k=1
weak: k=4 medium: k=32 strong: k=64
200 250 300
Step response
Figure 12-5 Smoothing with 2AI U Standard, 2AI U High Feature, 2AI I 2WIRE Standard,
2AI I 4WIRE Standard,
2AI I 2/4WIRE High Feature, 2AI RTD Standard, 2AI RTD High Feature, 2AI
TC Standard, 2AI TC High Feature