Key Technical Specifications
| Parameter | Detail |
|---|---|
| Part Number | IS230SNRTH2A |
| Product Type | RTD Input Terminal Board (S-Type) |
| Compatible System | GE Speedtronic Mark VIe |
| Input Type | RTD temperature sensors |
| Terminal Board Type | S-Type (simplex/non-TMR terminal board) |
| Interface | Connects to Mark VIe I/O pack via pack-to-terminal-board connector |
| Mounting | DIN-rail or cabinet-mounted terminal board |
| Application | Gas turbine temperature monitoring and protection |
| Redundancy | S-type; not a TMR terminal board |
| Operating Environment | Industrial turbine cabinet environment |
Product Introduction
In a Mark VIe turbine cabinet, the terminal board is the first point of failure that nobody checks. The IS230SNRTH2A is an S-type RTD terminal board. It does not execute control logic. It conditions RTD signals from the turbine casing, bearings, exhaust, or lube oil system and passes them to the mating Mark VIe I/O pack. If the terminal board develops a poor connection, a corroded terminal, or a failed conditioning circuit, the I/O pack sees bad temperature data even though the pack itself is healthy.The “S” in IS230S indicates a simplex terminal board configuration. That matters for replacement planning. A TMR temperature measurement uses three separate I/O packs and three separate terminal boards. Dropping an S-type board into a TMR point is acceptable only when it replaces the correct S-type terminal board in that channel. It is not a universal substitute for every Mark VIe RTD terminal board.
Quality SOP & Tech Pitfalls
The Lab Report (SOP)
- Visual inspection: verify GE labeling, part number IS230SNRTH2A, revision, and terminal block condition. Reject boards with cracked terminal blocks, burnt traces, or corrosion.
- Connector inspection: check the I/O pack interface connector for bent pins, oxidation, or loose solder joints.
- Continuity check: verify RTD input terminals to the pack connector for opens or shorts.
- Insulation check: verify no low-resistance paths between adjacent RTD channels.
- Mating verification: confirm compatibility with the site I/O pack before installation.
- Configuration capture: record board revision, serial number, slot location, and channel assignments.
Do not assume board-level functionality without the mating I/O pack. This terminal board is passive/conditioning hardware, not a standalone instrument.The Engineer’s Warning (Pitfalls)Aftermarket listings frequently misidentify IS230S terminal boards as Mark V or as active I/O modules. The IS230S family belongs to Mark VIe. If someone tries to use this board with a Mark V TCQA/TCQC architecture, it will not fit and it will not function.Another common mistake: replacing a T-type (TMR) terminal board with this S-type board. The physical connector may look similar, but the channel mapping and redundancy architecture are different. Also, RTD wiring errors at the terminal board are common after maintenance. A swapped lead or loose screw terminal produces a plausible but wrong temperature reading, which is more dangerous than an obvious fault.
Installation & Configuration Guide
Pre-Installation⚠️ Follow site lockout/tagout procedures before working in the turbine control cabinet.
⚠️ Photograph the existing terminal board, wiring labels, channel assignments, and I/O pack connection.
⚠️ Record which RTD channels map to which turbine measurement points.
Verify the replacement board revision matches the original and that the mating I/O pack is the correct type.RemovalLabel all RTD field wires. Disconnect field wiring from the terminal block. Release the I/O pack connector if required by site procedure. Remove the terminal board from its mounting.InstallationMount the IS230SNRTH2A in the same position. Reconnect the I/O pack interface. Reconnect field wiring to the correct terminals using the original labels. Verify torque on terminal screws. Check that no bare wire is exposed.Power-On & TestingRestore power to the I/O pack. Verify pack status LEDs. Check each RTD channel reading against known values or a calibrated simulator. Confirm no open-circuit or mismatch alarms. Monitor temperature trends for at least one full turbine operating cycle if the unit is online.
Compatible Replacement Models
| Compatibility Tier | Model | Notes |
|---|---|---|
| ✅ Drop-in Replacement | IS230SNRTH2A (same revision) | Match part number and revision; no rewiring needed |
| ⚠️ Same Family | IS230S RTD terminal boards (matching revision) | Verify channel count, terminal layout, and I/O pack compatibility |
| ⚠️ Functional Check Required | IS230S RTD boards with different suffix | May have different channel mapping or conditioning; verify against OEM documentation |
| ❌ Not Compatible | Mark V TCQA/TCQC boards, Mark VI VCMI/UR boards, non-RTD IS230 boards | Different platforms and signal types |
Frequently Asked Questions (FAQ)
Is IS230SNRTH2A an active I/O module?
No. It is a terminal board. The active signal processing is performed by the mating Mark VIe I/O pack.Can I use this in a TMR temperature measurement?
Only as the S-type terminal board for one channel of a TMR point. It does not replace a T-type TMR terminal board.What is the difference between S-type and T-type terminal boards?
S-type boards are simplex. T-type boards support TMR configurations with three redundant channels. They are not interchangeable.Why do some listings call this a Mark V board?
Because aftermarket descriptions are inconsistent. The IS230S prefix belongs to the Mark VIe terminal board family. Mark V uses a different architecture with TCQA/TCQC boards and I/O cores.Can I substitute a different IS230S RTD board?
Not without verifying the revision, channel count, terminal layout, and mating I/O pack. GE uses suffix letters to indicate hardware revisions and configuration differences.Do you provide calibration?
Standard supply includes visual inspection, continuity verification, and connection testing. RTD calibration and I/O pack configuration must be performed by qualified personnel using site procedures.
