Safety Considerations Guide for Trident v2 Systems - TUV ...

More documents

Recommendations

Info

6 Chapter 1 Safety Concepts As a required SIL capability increases, SIS integrity increases as measured by: • System availability (expressed as a percentage) • Average probability of failure to perform design function on demand (PFDavg) • Risk reduction factor (RRF, reciprocal of PFDavg) Determining a Safety Integrity Level If a PHA concludes that an SIS is required, ANSI/ISA S84.01 and IEC 61508 require that a target SIL capability be assigned. The assignment of an SIL capability is a corporate decision based on risk management and risk tolerance philosophy. Safety regulations require that the assignment of SIL capabilities should be carefully performed and thoroughly documented. Completion of a HAZOP determines the severity and probability of the risks associated with a process. Risk severity is based on a measure of the anticipated impact or consequences. On-site consequences include: • Worker injury or death • Equipment damage Off-site consequences include: • Community exposure, including injury and death • Property damage • Environmental impact • Emission of hazardous chemicals • Contamination of air, soil, and water supplies • Damage to environmentally sensitive areas A risk probability is an estimate of the likelihood that an expected event will occur. Classified as high, medium, or low, a risk probability is often based on a company’s or a competitor’s operating experience. Several methods of converting HAZOP data into SIL capabilities are used. Methods range from making a corporate decision on all safety system installations to more complex techniques, such as an IEC 61508 risk graph. Safety Considerations Guide for Trident v2 Systems
Sample SIL Calculation Hazard and Risk Analysis 7 As a PES, the Trident controller is designed to minimize its contribution to the SIL, thereby allowing greater flexibility in the SIS design. R I S K R E D U C T I O N 99.9999 Risk Measures 0.000001 99.999 0.00001 99.99 0.0001 99.00 0.01 90.00 0.1 Percent Availability Figure 3 Comparison of Percent Availability and PFD * Trident controller module failure rates, PFDavg, Spurious Trip Rate, and Safe Failure Fraction (SFF) calculation methods have been independently reviewed by TÜV Rheinland. The numbers presented here (and in the following tables) are typical. Exact numbers should be calculated for each specific system configuration. Contact the Invensys Global Customer Support (GCS) Center for details on calculation methods and options related to the Trident controller. The Triconex controller is a type-B safety-related subsystem as defined in IEC 61508-2 7.4.4.1.3. 3 Pressure Transmitters (2oo3) Sensors 3 Temperature Transmitters (2oo3) 99.90 0.001 SIL capability 3 SIS PFD Trident PES* Safety Integrated System TMR Controller (2oo3) PES/Logic Solver Figure 4 Simplified Diagram of Key Elements 2 Block Valves in Series (1oo2) Final Elements Safety Considerations Guide for Trident v2 Systems
Page 1 and 2: Trident v2 Systems Safety Considera
Page 3 and 4: Contents Preface vii Summary of Sec
Page 5 and 6: Contents v Partitioned Processes. .
Page 7 and 8: Preface This guide provides informa
Page 9 and 10: • All other requests are handled
Page 11 and 12: 1 Safety Concepts Overview 2 Hazard
Page 13 and 14: Protection Layers Methods that prov
Page 15: Hazard and Risk Analysis Hazard and
Page 19 and 20: Safety Life Cycle Model Hazard and
Page 21 and 22: Hazard and Risk Analysis 11 • Eac
Page 23 and 24: CAN/CSA-C22.2 No. 61010-1-04 Safety
Page 25 and 26: 2 Application Guidelines Overview 1
Page 27 and 28: General Guidelines This section des
Page 29 and 30: General Guidelines 19 Safety Measur
Page 31 and 32: Emergency Shutdown Systems The safe
Page 33 and 34: Safety-Shutdown Guidelines for Tric
Page 35 and 36: Guidelines for Triconex Controllers
Page 43 and 44: 3 Fault Management Overview 34 Syst
Page 45 and 46: System Diagnostics System Diagnosti
Page 47 and 48: Operating Modes Each input or outpu
Page 49 and 50: Analog Output (AO) Modules Module D
Page 51 and 52: Calculation for Diagnostic Fault Re
Page 53 and 54: External Communication Module Diagn
Page 55 and 56: 4 Application Development Developme
Page 57 and 58: Array Index Errors Infinite Loops D
Page 59 and 60: Setting Scan Time 49 application. T
Page 61 and 62: Sample Safety-Shutdown Programs Sam
Page 63 and 64: Sample Safety-Shutdown Programs 53
Page 65 and 66: When Some I/O Modules Are Safety-Cr
Page 67 and 68:
Sample Safety-Shutdown Programs 57
Page 69 and 70:
Partitioned Processes Sample Safety
Page 71 and 72:
Alarm Usage Alarm Usage 61 To imple
Page 73 and 74:
A Triconex Peer-to-Peer Communicati
Page 75 and 76:
Data Transfer Time Data Transfer Ti
Page 77 and 78:
Data Transfer Time 67 A typical dat
Page 79 and 80:
Examples of Peer-to-Peer Applicatio
Page 81 and 82:
B HART Communication Overview 72 HA
Page 83 and 84:
2008-04-01 Automation, Software and
Page 85 and 86:
2008-04-01 HART Position Paper from
Page 87 and 88:
2008-04-01 A possible impact to the
Page 89 and 90:
2008-04-01 HART Position Paper from
Page 91 and 92:
C Safety-Critical Function Blocks O
Page 93 and 94:
SYS_CRITICAL_IO Accumulates the sta
Page 95 and 96:
Library Trident and Tri-GP (TRDLIB)
Page 97 and 98:
END_IF ; PREVIOUS_RESET := RESET ;
Page 99 and 100:
Output Parameters (continued) Name
Page 101 and 102:
SYS_SHUTDOWN 91 * the safety system
Page 103 and 104:
ALARM_DISABLED_POINTS := MPX.POINTS
Page 105 and 106:
Example For shutdown examples, see
Page 107 and 108:
A abbreviations, list of viii actua
Page 109 and 110:
message errors, external communicat
Page 112:
Invensys Operations Management 5601
show all

Safety Considerations Guide for Trident v2 Systems - TUV ...

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?