9 Reliability, Availability and Safety of Electronic Control Systems
9.1 Reliability of Electronic Control Systems . . . . . . . . . . . . . . . . . . . . . . . . 9 - 1
9.1.1 Failure Characteristics of Electronic Devices . . . . . . . . . . . . . . . . . . . . . 9 - 2
9.1.2 Reliability of SIMATIC S5 Programmable Controllers and
Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 - 2
9.1.3 Failure Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 - 3
9.2 Availability of Electronic Control Systems . . . . . . . . . . . . . . . . . . . . . . 9 - 3
9.2.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 - 3
9.2.2 Availability of the S5-115F Programmable Controller . . . . . . . . . . . . 9 - 4
9.3 Safety of Electronic Control Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 - 5
9.3.1 Safe Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 - 5
9.3.2 Safe Binary Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 - 6
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