Product Core Brief

• Model: IS230TVBAH2A
• Brand: General Electric (GE)
• Series: Mark V (Speedtronic)
• Core Function: Scales and conditions analog signals from terminal boards for gas turbine control — LVDT, servo valve, thermocouple, 4-20mA, vibration, pulse, voltage, relay driver, and generator/line signals.
• Product Type: RST Analog I/O Board (TCQA)
• Key Specs: 3PL data bus to STCA | JE connector to TCQC | JD trip signal output | 2PL power distribution | -30°C to 65°C operating range
• Condition: New Original / New Surplus

Product Introduction

The GE IS230TVBAH2A is a TCQA analog I/O board in GE’s Mark V Speedtronic turbine control system. It’s mounted in the I/O core (R1, R2, or R3) and handles scaling and conditioning of analog signals read from terminal boards — including LVDT position inputs, servo valve outputs, thermocouple signals, 4-20mA loops (such as compressor stall detection and fuel flow pressure signals), vibration inputs, relay driver outputs, pulse inputs, voltage inputs, and generator/line signals.

Conditioned signals are routed to the STCA board via the 3PL data bus connector over the COREBUS link. The JE connector exchanges generator/line signals, pulse signals, relay driver outputs, and servo valve driver outputs with the TCQC board. The JD connector sends trip signals to the TCTG board in the core. Power is distributed from the TCPS board through the 2PL connector to the entire I/O core.

This board is a critical link in the Mark V control chain — it translates raw field signals into digitized values the controller can use for turbine protection logic, closed-loop regulation, and process monitoring.

Key Technical Specifications

Quality Control Process

Every IS230TVBAH2A goes through a full functional bench test before it ships. We start with a visual PCB inspection — checking for cold solder joints, burnt traces, swollen capacitors, and corrosion on all connector headers (2PL, 3PL, JD, JE, JF, JG, JA). Mark V boards often run for decades in turbine enclosures where condensation and temperature cycling take a toll on older components.

Then we power it up on a regulated DC supply and verify the 2PL power rail voltages are within spec. We inject calibrated 4-20mA signals through the JB connector and measure the conditioned output on the 3PL data bus with a Fluke 754 process calibrator, confirming scaling accuracy. We test LVDT excitation voltage and position input scaling via the JF connector, thermocouple input channels via JA, and ±10V DC inputs via JG. We verify the JD trip signal path by simulating a trip condition and confirming the signal routes correctly to the TCTG board interface. Finally, we confirm the 3PL data bus communication with the STCA board by verifying the board responds with its hardware ID packet. Each unit ships in anti-static foam with a moisture barrier bag.

Replacement Pitfall Guide

❗ Verify your terminal board pairing. The IS230TVBAH2A (TCQA) works with specific terminal boards — TBQA for thermocouple inputs (JA connector), TBQC for 4-20mA and LVDT signals (JB/JF connectors), and TBQB for ±10V DC and vibration inputs (JG connector). If you’re replacing a failed TCQA board but your terminal board is damaged or mismatched, the new board won’t read field signals correctly.

❗ Check the JD trip signal pinout before connecting. The JD connector carries trip signals from the core to the TCTG board — this is safety-critical wiring. If you’re cross-wiring from a different TCQA revision, a pinout change can bypass trip logic entirely. Always compare the wiring diagram on your existing board’s label against the replacement before making connections.

❗ Confirm 3PL data bus communication after installation. The 3PL connector routes conditioned signals to the STCA board via COREBUS. If the replacement board doesn’t respond with its hardware ID packet after installation, the Mark V controller won’t recognize it and the I/O core will fault. Verify communication before closing the panel.

❗ Watch backplane power headroom. The 2PL connector distributes power from the TCPS board to the entire I/O core. If you’re adding a new TCQA board without verifying remaining headroom, you can cause brownouts on adjacent modules — especially if multiple boards are driving servo valve outputs or relay loads simultaneously.

❗ Don’t skip the cold-end compensation check. Thermocouple inputs rely on cold-end compensation (CEC) from the TBQA board. If the replacement TCQA board reports a different baseline temperature than the original, you may get inaccurate thermocouple readings or nuisance temperature alarms. Verify CEC calibration after installation.

Keep these in mind and you’ll cut 90% of rework time.

Compatibility Matrix & Benchmarks

• Signal Conditioning Range: 4-20mA analog loops, ±10V DC inputs, thermocouple types J/K/T/E, LVDT position feedback
• Data Bus Throughput: 3PL COREBUS link to STCA board with hardware ID packet response