Safety block diagrams
The components that are included in the safety data calculations are
shown in the safety block diagrams below.
Note: The failure rate of the PTC sensor is not included in the
calculations.
■ Two-channel configurations
This diagram is applicable to configuration 1.
PTC sensor1
FPTC module2
Drive STO3
This diagram is applicable to configuration 2.
PTC sensor1
FPTC module2
FSO module3
Drive STO4
84 Technical data