GE IS230PCAAH1A Mark VIe PCCA Core Analog Module

The GE IS230PCAAH1A is a PCCA Core Analog Module designed for the Mark VIe distributed control system. It processes analog field signals used in gas turbine control, including thermocouple measurements, 4-20 mA inputs, LVDT signals, pulse rate inputs, and servo coil outputs. The module combines processor and application I/O circuitry in a single assembly and supports simplex, dual, and TMR system configurations.

Analog Signal Processing

The PCAA assembly contains a processor board, two application-specific analog processing boards (BCAA and BCAB), and an integrated TCAS terminal board. The acquisition circuitry performs signal conditioning and analog-to-digital conversion before transferring measurement data to the Mark VIe control processor.

Its signal interfaces cover several measurement and control functions:

• Thermocouple inputs for temperature measurement.
• 4-20 mA current-loop inputs for process instrumentation.
• Configurable 4-20 mA or +/-10 V analog inputs.
• LVDT excitation and feedback for actuator position measurement.
• Seismic and vibration inputs through the associated terminal interface.
• Pulse-rate inputs for flow measurement.
• Servo coil driver outputs and analog current outputs.

The combination of measurement and output circuits allows the PCAA to handle both field feedback acquisition and selected turbine control output functions within the same hardware assembly.

Processor and Communication Interface

The processor board includes RAM, flash memory, a hardware watchdog timer, a reset circuit, local temperature sensing, status LEDs, and an infrared serial communication interface. Its electronic identification function checks the installed processor, acquisition, and terminal board identities during initialization.

Two independent 10/100 Ethernet ports provide communication with the Mark VIe IONet. When both network connections are used, both paths remain active. The module also monitors its internal power supplies and uses a soft-start and current-limiting circuit when 28 VDC power is applied.

Terminal Board and System Configuration

The integrated TCAS terminal board routes field signals to the BCAA and BCAB processing boards. An optional TCAT Core Analog Terminal Board provides additional terminals and distributes selected input signals to multiple PCAA modules.

A single TCAT can distribute signals to one, two, or three PCAA modules, depending on the system architecture. This arrangement supports simplex, dual, and triple modular redundant (TMR) configurations. If the application does not require fanned inputs, the PCAA can operate without the optional TCAT board.

Technical Specifications

Installation and Connection Requirements

The PCAA module receives its 28 VDC supply through connector P5. Connector P4 supplies power to the adjacent JGPA ground and power board. Field wiring connects through the module's Euro-style terminals.

When a TCAT terminal board is installed, connect it to PCAA using both 68-pin cables at P1 and P2. The cable connections must correspond to the controller network assignment:

• PR1 and PR2: R controller network.
• PS1 and PS2: S controller network.
• PT1 and PT2: T controller network.

Fully seat the cable mounting screws and tighten them by hand. Proper cable grounding is required for PCAA to read the TCAT electronic identification correctly and maintain signal quality.

For a single IONet connection, either Ethernet port can be used. In dual-network configurations, ENET1 is normally connected to the R controller network. In TMR configurations, the PCAA network assignment must match the corresponding TCAT cable connections.

Frequently Asked Questions

Q: Can the IS230PCAAH1A operate without a TCAT terminal board?

A: Yes. TCAT is optional in simplex configurations when signal distribution to multiple PCAA modules is not required. The integrated TCAS terminal board provides the module's internal signal routing.

Q: Can the IS230PCAAH1A be used in a TMR configuration?

A: Yes. The PCAA supports TMR operation with three modules connected through a TCAT terminal board. Each module must use the corresponding R, S, or T controller network connection.

Q: Can individual circuit boards inside the IS230PCAAH1A be replaced?

A: No. GE identifies the complete PCAA assembly as the minimum replaceable unit. The processor board, BCAA, BCAB, and TCAS are not intended for individual field replacement.