Masoneilan Products SVI II ESD - GE Energy

GE Energy
SVI II ESD Device Description
SVI II ESD Quick Start
An ESD valve is a valve that is operated to ensure that the process is brought to
its safe state. During normal operation, these ESD valves are typically energized
to stay open. In case of an unsafe situation, the ESD valve is de-energized by the
Safety System. The SVI II ESD device performs this shutdown function for Safety
Instrumented Functions (SIF) that require field devices to be certified for safety
related applications according to IEC61508 and is certified by TUV for use up to
SIL3 with a HFT of 0 in low demand applications. It is important to note that the
built-in microprocessor is used for valve diagnostics only. The microprocessor has
no direct role in performing the designated safety function therefore the SVI II
ESD is considered a Type A device.
The SVI II ESD is a valve controller that mounts on a pneumatically actuated
valve assembly. Its role is to position an emergency shutdown valve to 0% or
100% with a PFDavg in accordance with IEC61508 for SIL3 application.
Because of its capability of monitoring data from its embedded sensors, the SVI II
ESD is capable of validating the health of its integral components. Also, with the
ability of partially stroking the ESD valve while in normal operations (energized to
stay open); it becomes possible to validate the health of the valve and actuator
assembly. Periodic testing of the ESD valve reduces the PFDavg by detecting
dangerous failures.
Designing an SIF Using an SVI II ESD
The following must be taken into consideration when designing a SIF (Safety
Instrumented Function) using the SVI II ESD:
“Safety Function” on page 7
“Environmental Limits” on page 7
“Design Verification” on page 7
“SIL Capability” on page 8
“Connecting the SVI II ESD to the SIS Logic Solver” on page 9
“General Requirements” on page 9
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