Siemens Simatic M7-400, Справочное руководство

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Analog Modules
5-37
S7-400, M7-400 Programmable Controllers Module Specifications
A5E00069467-07
Example
The following figure shows the number of module cycles for a step response after
which the smoothed analog value is approximately 100% applied, as a function of
the smoothing that has been set. The figure applies to every change of signal at
the analog input.
50
100
0
63
50 100
150 200
Smoothing: low:
average:
high:
Module cycles
Signal variation
in percent
Step response for any analog input signal
Figure 5-5 Example of the Influence of Smoothing on the Step Response
Additional Information on Smoothing
Refer to the specific section on the analog input module (from Section 5.18) to
determine whether smoothing can be set for the specific module and for any
special features that have to be taken into account.
Conversion Time of the Analog Output Channels
The conversion time of the analog output channels comprises the transfer of the
digitized output values from the internal memory and the digital-to-analog
conversion.
Scan Time of Analog Output Channels
The analog output channels are converted sequentially – in other words, the
analog output channels are converted one after the other.
The scan time – in other words, the time elapsing until an analog output value is
again converted – is the sum of the conversion times of all activated analog output
channels (refer to 5-4).