© 2018 Baker Hughes, a GE company, LLC. All rights reserved.
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Systematic Integrity
The product has met manufacturer design process requirements of Safety Integrity Level (SIL) 3.
These are intended to achieve sufficient integrity against systematic errors of design by the
manufacturer. A Safety Instrumented Function (SIF) designed with this product must not be used
at a SIL level higher than the statement without
prior use
justification by end user or diverse
technology redundancy in the design.
Random Integrity
The SVI II ESD’s safety critical function is maintained by a Type A Device. Therefore based on the
SFF > 90%, when the SVI II ESD is used as the only component in a final element subassembly, a
design can meet SIL 3 @ HFT=0.
When the final element assembly consists of many components (SVI II ESD, quick exhaust valve,
actuator, isolation valve, etc.) the SIL must be verified for the entire assembly using failure rates
from all components. This analysis must account for any hardware fault tolerance and architec-
ture constraints.
Safety Parameters
For detailed failure rate information refer to the Failure Modes, Effects and Diagnostic Analysis
Report for the SVI II ESD available from the factory.
Connecting the SVI II ESD to the SIS Logic Solver
When connecting the SVI II ESD to the SIS logic solver follow these guidelines:
The SVI II ESD is connected to the safety rated logic solver which is actively
performing the safety function. Connections must be made per the
instructions supplied by the safety rated logic solver.
The output rating of the I/O module must meet or exceed the electrical
specifications of the SVI II ESD as referenced in ES727 (“Hazardous Location
Installation” on page 78).
