Administración De Instrumentos

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AMS Safety Analysis
Using AMS in Safety Instrumented System Applications

Project:
AMS Safety Analysis
For:

Emerson Process Management
Fisher-Rosemount Systems, Inc.
12001 Technology Drive
Eden Prairie, MN.

Contract No.: Q03/03-09
Report No.: R03/03-09 R001
Version V1, Revision R1.0, May 23, 2003

The document was prepared usingbest effort. The authors make no warranty of any kind and shall not be liable in any
event for incidental or consequential damages in connection with the application of the document.
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Management summary
Emerson Process Management’s AMS system can be effectively used to meet many of the
requirements of IEC 61511 insafety instrumented system applications. In such an application the
AMS system is considered “non-interfering” and is not part of the safety function.
AMS can be effective in SIS installation and commissioning, SIS maintenance, SIS modification
and the design requirements associated with those phases of the safety lifecycle. Features of
AMS including individual login security, automatic audittrail and SNAP-ON diagnostics will allow
the user to meet specific safety lifecycle requirements. The system as reviewed was created with
a HART multiplexer.
For SIS installation and commissioning, AMS allows the user to verify proper setup and operation
of field instruments. AMS increases effectiveness of operation and maintenance (mechanical
integrity) programs. Remote diagnosticcapabilities allow periodic p
roof tests to be performed
thereby extending the time period between off-line proof tests. During SIS modification, AMS can
be used to compare new configurations with previous configuration. This id done to confirm that
only changes per the update plan were made and that they were made correctly.
Compared to current practices, AMS usage should be less error prone andclearly traceable.
Two important things must be done to insure system safety with AMS. The AMS system must be
setup with individual password security for those authorized to perform SIS maintenance and
modification activities. Procedures must be established to insure proper usage of the 275
handheld communicator. In addition during design verification, the failure rates of the HART
multiplexermust be accounted for in the probabilistic analysis of each SIF.

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ams in safety reportb, May. 24, 2003
Page ii of i ii

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Table of Contents
Management summary...............................................................................................ii
1

Purpose andScope............................................................................................. 2

2

Project management ........................................................................................... 2
2.1 exida.com ........................................................................................................................ 2
2.2 Roles of the parties involved............................................................................................. 2
2.3 Standards used ................................................................................................................. 2
2.4 Reference documents ....................................................................................................... 2
2.4.1 Documentation provided by the customer.............................................................. 2
2.4.2 Industry References ............................................................................................... 3

3

System Description............................................................................................. 4

4

AMS Usage per IEC 61511 requirements.............................................................. 5
4.1 SIS Design and...