SIL verification is one of the important activities of functional safety life cycle. For a Safety instrumented function (SIF), appropriate hardware (Sensors, logic solver and final elements) is selected and configured to meet safety requirement specification (SRS) of the SIF.
SIF loop configuration needs to be evaluated to check and ensure that it meets the SIL level, RRF and other requirements of SRS. Various modelling techniques may be used for evaluation. Since calculations are complex and time consuming, various software/tools are available in the market.
SILcet 5.2 Pro Plus is an Excel workbook for carrying out SIL Verification. This versatile and user-friendly tool is very useful for carrying out SIL verification of simple as well as complex SIFs. Up to 70 SIFs can be verified in a single workbook which is more than enough for any project. If required, one can have multiple workbooks for any project. The user can also create a database with the elements used in the project that include failure rates, type of element, cost, systematic capability, etc
Advantages:
1) Excel workbook uses formulas and macros, hence can be used on any Desktop / Laptop, no need of login/password or internet connection.
2) Calculates SIL (Safety Integrity Level) of the SIF taking into account the three requirements contemplated in IEC-61508 / IEC—61511 Standards (systematic capability, probability of failure and architectural constraints).
3) Architectural constraint table can be selected as per Route 1H or Route 2H or IEC 61511 Route.
4) SIFs can be copied/edited/modified. This saves lot of time.
5) Comparison of SIL calculations of different SIF designs can be made.
6) Three types of Reports can be generated including logic diagram of the architecture of each SIF.
7) Excellent e—mail support for any queries/suggestions
Having used SILcet 5.2 Pro Plus for last few years, I find this tool very useful and fit for the purpose. The annual cost is just a fraction of the cost of other tools available in the market.
For more details, visit: SIL Verification Tool-Functional Safety (Safetyandsis.com)
Process & Safety Consultant 