Siemens SIMATIC S7-400 Reference Manual page 300

Analog modules
5.24 Analog input module SM 431; AI 8 x RTD x 16 Bit (6ES7431-7KF10-0AB0)
Parameters
● Temperature coefficient for
temperature measurement
with thermal resistance (RTD)
● Noise suppression
Smoothing
If you use the module in ER-1/ER-2, you must set this parameter to "No" because the interrupt lines are not available in
1
ER-1/ER-2.
Only in the CR (central rack) is it possible to start up the analog modules with the default settings.
2
The limit values must be within the temperature range of the connected sensor.
3
Measured value smoothing
You will find information that is generally applicable to the smoothing of analog values in the
respective section.
The following figure shows for the module the number of module cycles, in the case of a step
response, after which the smoothed analog value is applied to almost 100%, depending on
the smoothing setting. The figure applies to every change of signal at an analog input.
Signal variation in
percent
Smoothing
Figure 5-37
300
Value range
For platinum (Pt)
0.00385 Ω/Ω/ °C
0.003916 Ω/Ω/ °C
0.003902 Ω/Ω/ °C
0.003920 Ω/Ω/ °C
For nickel (Ni)
0.00618 Ω/Ω/ °C
0.00672 Ω/Ω/ °C
60 Hz; 50 Hz; none
None
Weak
Medium
Strong
Step response for any analog input signal
100
63
50
0 20
Low:
average:
high:
Step response of the SM 431; AI 8 x RTD x 16 Bit
Default
2
0,00385
60 Hz
None
40 60
S7-400 Automation System Module Data
Reference Manual, Ausgabe 11/2016, A5E00850736-08
Parameter Scope
type
Static Channel
Static Channel
80 100
Module cycles