Product Description

The TPS02 is a dedicated turbine protection interface module developed by ABB Bailey for integration into INFI 90 and Symphony Plus distributed control systems. It functions as a safety-critical slave unit that directly interfaces with turbine emergency trip circuits, enabling ultra-fast response to overspeed or process fault conditions in steam and gas turbine applications.

Unlike general-purpose I/O modules, the TPS02 operates on a deterministic hardware-level logic path, bypassing standard system scan cycles to guarantee sub-millisecond trip activation when thresholds are exceeded. It continuously monitors redundant speed sensor inputs (typically from magnetic pickups or proximity probes) and hardwired trip signals, then drives high-integrity relay outputs that trigger solenoid valves or breaker coils in the turbine shutdown train.

Technical Specifications  

• Manufacturer: ABB (formerly Bailey Controls)

• Model / Part Number: TPS02

• Compatible Systems: INFI 90, Symphony Plus (with appropriate expander hardware)

• Module Type: Turbine Protection System (TPS) Slave

• Mounting: Occupies one slot in a standard Module Mounting Unit (MMU)

• Power Supply: +5 VDC via backplane (no external power required)

• Communication Interface: Dedicated Slave Expander Bus (SEB)

• Input Channels:

• 2–4 redundant overspeed detection inputs (accepts AC/DC tachometer or pulse signals)

• Multiple hardwired trip request inputs (voltage-free contacts or 24 VDC logic)

• Output Type: Solid-state drivers energizing fail-safe trip relays (external or internal)

• Trip Logic: Hardwired or firmware-configurable voting logic (e.g., 2oo3 overspeed)

• Operating Temperature: 0 °C to +70 °C (non-condensing)

• Diagnostic Features: Built-in self-test (BIT), watchdog timer, and status reporting to master controller via SEB

• Safety Isolation: Optical or transformer-based isolation between logic and field-side trip circuits

• Certifications: Designed to meet IEC 61508 SIL 2/3 requirements in properly architected systems

Typical Applications  

• Emergency overspeed protection in fossil, nuclear, and combined-cycle power plants

• Integration with mechanical-hydraulic trip systems requiring electronic backup

• Retrofit projects upgrading legacy turbine controls to digital DCS platforms

FAQ
Q: Can the TPS02 operate independently of the Symphony Plus controller?
A: No—it requires a master module (such as the TPS01) on the same expander bus to configure logic and monitor health, though trip execution is hardware-accelerated and does not rely on host CPU cycles.

Q: Does it support triple-modular redundancy (TMR)?
A: The TPS02 itself is a single-channel module, but multiple units can be deployed in redundant configurations (e.g., 2oo3 voting across three TPS02 modules) when paired with appropriate input/output hardware and logic.

Q: How is diagnostics information accessed?
A: Status bits (OK, fault, trip active) are communicated over the Slave Expander Bus to the master protection module, which forwards them to the DCS operator station for alarm annunciation and logging.