Quick Sizing & Sourcing Snapshot
- Manufacturer: GE (General Electric / Emerson)
- Part Number: IS230TCATH1A
- System Platform: Mark VIe / Mark VIeS (Speedtronic)
- Hardware Type: Core Analog Terminal Board Assembly (TCAT)
- Architectural Role: Acts as the passive field termination hub for analog signals, fanning out seismic, LVDT, and 4-20mA inputs to one or three PCAA I/O packs.
- Key Specifications: 12 Seismic / 12 LVDT / 24 AI, 120 Euro Terminals, 68-pin to PCAA, 28V DC Powered.
System Architecture & Operational Principle
The IS230TCATH1A is a passive TCAT (Core Analog Terminal) board, forming the field-facing interface for analog signals in a Mark VIe rack. It doesn’t run code; it mounts on a DIN rail (metal base with plastic carrier) and bridges sensors to the active PCAA I/O packs.
Physically, it hosts 120 pluggable Euro-style terminals (grouped 48/24/48). Field wires (LVDTs from fuel valves, Seismic sensors on bearings, 4-20mA pressure transmitters) land here. The board uses passive circuits (jumper-configured) to condition signals and “fan out” the data: in TMR, the same field signal is routed via 68-pin cables to three PCAA packs (R, S, T via PR1/PS1/PT1 connectors). This ensures a wiring fault on one leg doesn’t kill the vote. It draws 28V DC and 15V DC from the connected PCAA to power onboard 24V regulators for transmitter excitation. It operates at Level 1, ensuring high-impedance analog signals are conditioned close to the source before hitting the digital IONet backbone.
Core Technical Specifications
- Input Channels: 12 Seismic, 12 LVDT (Position), 24 4-20mA, 2 Pulse Rate
- Output Channels: 3 Voted 4-20mA (Hardware voted via PCAA logic)
- Power I/O: 28V DC & 15V DC (Sourced FROM PCAA via 68-pin)
- Excitation: 12x 24V DC @ 25mA (On-board reg for 4-20mA loops)
- Terminals: 120 Pluggable Euro-Style (Groups: 48, 24, 48)
- I/O Pack I/F: 2x 68-pin (PR1/PR2, PS1/PS2, PT1/PT2 to PCAA)
- Adjacent Board: JGPA (Provides shield grounds + 12x 24V DC outputs)
- Config: Jumpers per channel (2-wire/3-wire LVDT, Source/Sink, Return)
- Isolation: Channel-to-Channel (Via PCAA Optos), Passive Trace Isolation
- Mounting: DIN Rail (TS-35) via Metal Carrier (Insulating shim)
- Environmental: -30°C to +65°C, Conformal Coated
Customer Value & Operational Benefits
Centralized Analog Management
Consolidates LVDT, Seismic, and 4-20mA into one high-density block. All turbine “health” signals (valve position, vibration, pressure) sit in one spot. During a trip, you correlate LVDT position vs. Seismic spike without tracing wires across three boards, slashing root cause analysis time by 30-50%.
