SIS-Tech has introduced the Diamond-SIS automated independent backup (AIB), a safety instrumented system (SIS) that backs up current process control trip logic and meets the requirements of IEC 61511. The system includes an IEC 61508 logic solver that is functionally independent from the process control system, supplements existing logic, and meets all appropriate safety standards. It is available in single, dual, and triplicated channel configurations with on-line diagnostics, testing, and maintenance capabilities. The single and dual channel systems are acceptable for SIL 2, while the triplicated channel system is certified by Factory Mutual to SIL 3. This means that Diamond-SIS can meet the fault tolerance and PFavg requirements of any application. With its 5A output rating, the system can de-energize multiple final elements including motor control circuits and/or solenoid operated valves. Local or remote manual reset ensures controlled process re-start after shutdown. A single channel Diamond-SIS AIB system includes a pre-mounted and wired DIN-rail signal isolator, a Model 340 logic solver, a fuse block, and five terminals ready to accept existing wiring. All components are rated for -30 to 75C and Class I Div II operation, and meet the mechanical integrity requirements of IEC 61511.
