Emerson El-O-Matic E Series - Assembly and Installation Procedures; Actuator Mounting and Installation

Hardware Fault Tolerance
Section 8: Hardware Fault Tolerance
The HFT of the device is 0.
The requirements of minimum hardware fault tolerance (HFT) according to Tab.6 of IEC
61511-1 have to be observed but, as long as has been performed an assessment report
fully in compliance with IEC 61508 part 1 to7, alternative fault tolerance requirements
have to be considered applicable according to Table 2 of IEC 61508-2 as per par. 11.4.5
of IEC 61511-1.
SIL Safety Manual
DOC.SILM.EEP.EN Rev. 0
April 2017
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Section 8: Hardware Fault Tolerance