In general SIS vendors has thier own Safety Communication Certified by TUV, which can be used upto SIL3.

How about Modbus Communication?

Is any SIS PLC vendor (Like Triconix, Emerson, Hima, Triplex) use Modbus as approved TUV certified safety communication?

Whether Modbus Data cab be used as part of SIS logic (executive action cause plant/equipment shutdown)?

Please share your expertise..

Thanks

 

I do not think so. MODBUS is not deterministic.

 

No MODBUS is not a safety related or certified communications protocol. This may change in the future with the development of Open Safety, a method of encapsulating protocols within a safety related transport protocol.

 

My understanding of certifications is that no protocol (or anything else for that matter) is certified based on the specification it claims to use. Only actual implementations can be certified. That is, just because vendor 'A' had their system certified doesn't mean that vendor 'B' automatically becomes certified even if they claim to be using the same protocol. Each vendor has to get their own certifications for each product.

You would need to contact each vendor and ask them what certifications they have. You can't go by generic feature checklists.

I think you will also find that controls are certified as a package. If you mix and match certified and non-certified components, then the system as a whole is non-certified.