Siemens SIMATIC PCS 7 Configuration page 54

3 Configuring the redundant peripherals
3.6 Additional parameter settings for the configuration of the redundant AI modules
The factor 2 is the smallest factor that may be used. If the process conditions allow
a higher value, the factor can also be 3 or 4.
Table 3–8. Examples
50 Hz, 1 channel, TPA = 500 ms
50 Hz, 4 channels, TPA = 500 ms
50 Hz, 8 channels, TPA = 500 ms
10 Hz, 8 channels, TPA = 50 ms
In the event that two different integration times are assigned to the channels of
Note
a module (10 Hz and 50 Hz), the worst case is calculated. This means that the
calculation is performed with 10 Hz.
Tolerance window
Depending on the quality of the field signal, a tolerance range of 5% to 20% should
be set.
General time or cycle assessment
The redundant modules may only be accessed via the process image.
For more information on how to configure the I/O modules, please refer to
chapter 3.5 "Signal module settings".
The same process image partition must be assigned to both modules of
a redundant pair.
The relevant channel blocks should either have the same cycle time as the process
image process image partition or have their cycle slowed down. No advantage
is gained from being faster than the process image partition.
Configuration of Redundant I/O Modules
Entry-ID: 28430682, V2.0,
Parameter
03/2015
Discrepancy time to be set
1130 ms
1520 ms
2040 ms
5880 ms
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