Siemens SIDOOR ATD401W System Manual page 95

Antivalent connection of two redundant, two-channel antivalent sensors to two channels
Two redundant 2-channel antivalent sensors are needed for the signal (1oo2 evaluation)
Figure 3-15
ATD4xxW Door Controller for Industrial Applications
System Manual, 01/2017, A5E38080677-AB
Two-hand control device example
SIDOOR functions
3.4 Safety functions
95