API 14C (1998), API 521 (1997), and Code Case 2211 (1995) of ASME Section VIII, Division 1 and 2, provide alternatives in the design of overpressure protection systems. These alternatives revolve around the use of an instrumented system that achieves a level of safety that meets or exceeds the...
Every redundant technology PLC that I know of has "D" diagnostics built in. In 1oo2D systems if there is a disagreement how do you determine which one is bad? In 2oo3D systems you have a better chance of determining which channel/input is bad.
Triconex provides 1131 compliant programming software with ladder logic, function blocks, cause and effect matrix, and structured text. http://triconex.com/
There currently two Triconex platforms (Tricon and Trident) that use the same utility software.
Thanks Rob, I'm very familiar with IEC 61508/61511 and ISA S84. Quantitative Risk Assessment is the primary part of my job. I'm actually looking for a good source of testing procedure recommendations for valves. The "frequencies" portion of the posting should not have been there. I...
