TRICONEX PI 3351 – High‑integrity Pulse Input Module for Tricon TMR Safety Systems

Turbine and compressor overspeed monitoring with TMR voting for SIL‑level protection.

Flow metering and totalization (mag meters, turbine meters) in oil & gas and chemicals.

Machine speed feedback in rotating equipment skids and packaged systems.

Power generation balance‑of‑plant speed/ratio measurements.

Emergency shutdown (ESD) and process safeguarding where pulse signals drive trips or permissives.

Reliability in critical loops – The TMR structure and diagnostics mean a single‑leg fault is usually tolerated without losing measurement integrity.

Lifecycle continuity – Broad installed base and consistent form factor help with long‑term support and spares strategy.

Integration simplicity – Works natively with TriStation engineering tools; no special gateways needed inside the Tricon chassis.

Cost control – Hot‑swap capability and straightforward termination assemblies can reduce service time and commissioning risk.

Panel/cabinet: Use a clean, ventilated cabinet; maintain airflow around the Tricon chassis. Keep ambient within the specified temperature range.

Wiring: Use shielded twisted pair for pulse lines, especially for low‑level sensors. Terminate shields at a single ground point to limit noise.

Separation: Route pulse/signal wiring away from high‑energy cables and drives; add surge protection for outdoor sensors where appropriate.

Termination assembly: Match the PI 3351 to the correct terminal board and cable set; verify jumper/debounce settings in accordance with the sensor type.

Commissioning: Validate channel scaling, edge detection, and any frequency filtering in TriStation before startup. Document channel mapping for each leg (A/B/C).

Routine care: Periodically check terminal tightness, clean dust with dry air, and review diagnostics. Firmware and module revisions should be aligned across the three legs.

Safety: De‑energize field circuits where possible; follow site lockout/tagout procedures when moving I/O cabling or handling modules.

Designed for use in SIL3 safety instrumented systems when applied within the Tricon architecture (TÜV assessed under IEC 61508/61511).

CE compliance and UL/CSA recognition are typically available for Tricon system components; verify per module revision.

RoHS alignment applies to most recent revisions; confirm if your site has strict material declarations.

Standard manufacturer warranty is commonly 12 months from shipment; extended coverage can be arranged through service agreements.