Siemens SIMATIC PCS 7 CPU 410-5H System Manual page 69

System configuration and project engineering
You should allocate switched I/O with different changeover times to separate chains. This,
for example, simplifies the calculation of monitoring times.
See also
Time monitoring (Page 123)
CPU 410-5H Process Automation
System Manual, 09/2014, A5E31622160-AB
I/O configuration variants
4.5 Using single-channel switched I/O
69