Parameters
Value range
Default
2
Parameter
type
Scope
● Temperature unit
4
Degrees Celsius; degrees Fahren‐
heit
Degrees Celsius
Static
Module
● Noise suppression
400 Hz; 60 Hz; 50 Hz; 10 Hz
60 Hz
● Smoothing
None, weak, medium, strong
None
● Reference junction (reference
to the cold junction)
None
Internal
Reference temperature value dy‐
namic
Internal
Static
Module
1
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
ER-1/ER-2.
2
Only in the CR (central rack) is it possible to start up the analog modules with the default settings.
3
The limit values must be within the temperature range of the connected sensor.
4
Valid for the format of the output temperature and the dynamic reference temperature
Measured value smoothing
For generally valid information on analog value smoothing, refer to the section "Conversion
and cycle and response times of analog modules".
The cycle time of the module is a constant in the SM 431; AI 8 x 16 Bit that is not dependent
on the number of channels that are enabled. It therefore has no effect on the step response,
which is defined by the parameter assignment of interference frequency suppression and
smoothing.
Step response
Table 5-72
How response times depend on the configured interference frequency suppression and smoothing of the SM
431; AI 8 x 16 Bit
Interference frequency sup‐
pression in Hz
Response time in ms with configured smoothing:
None
Weak
Medium
Strong
10
100
200
1600
3200
50
20
40
320
640
60
16,7
33,3
267
533
400
10
20
160
320
The following figures illustrate the contents of table above. They show the response time
required for a step response before the smoothed analog value is almost applied to 100%.
The figures apply to every change of signal at an analog input.
Analog modules
5.25 Analog input module SM 431; AI 8 x 16 Bit (6ES7431-7KF00-0AB0)
S7-400 Automation System Module Data
Reference Manual, Ausgabe 11/2016, A5E00850736-08
311