Key Technical Specifications
| Parameter | Specification |
|---|---|
| Model | IS200TURH1BED |
| Product Family | GE Speedtronic Mark VIe TURH Terminal Board |
| Board Type | Turbine Regulation Terminal Board |
| Typical Paired Boards | IS200VTURH1B (VTUR), IS200PTURH1x (PTUR) |
| Configuration Mode | TMR or Simplex (jumper-selectable) |
| Onboard Components | Relays, transformers, variable resistors, ICs, D-sub connectors |
| Communication Interfaces | D-sub connectors, terminal blocks, backplane interface |
| Primary Functions | Speed signal routing, overspeed trip relay interface, generator sync signals, flame detector interface (via VTUR) |
| Mounting | Standard Mark VIe cabinet slot / backplane mount |
| Typical Applications | GE gas/steam turbine control, Mark VIe Simplex/Dual/TMR systems |
Product Introduction
IS200TURH1BED is the terminal board that sits behind the VTUR or PTUR processor in a Mark VIe turbine cabinet. If the VTUR board is the brain that calculates speed, detects overspeed, and monitors flame detectors, the TURH board is the nervous system that routes those signals in and out — trip relays, speed pickups, generator sync signals, and configuration jumpers.Engineers keep this board in the spare cabinet because a failed relay contact or corroded connector on the TURH can trip a turbine just as effectively as a processor fault. The TMR/Simplex jumper setting is one of those details that gets overlooked during a midnight swap — if the jumper does not match the system architecture, the board will not pass the expected signals and the controller will fault. The onboard relays and transformers are robust, but they are not immune to years of vibration, thermal cycling, and moisture ingress. After a web break or a major trip event, inspect the TURH connectors and relay seating alongside the processor board.
Quality SOP & Tech Pitfalls
The Lab Report (SOP)
- Nameplate verification: Confirm “IS200TURH1BED” exactly. Distinguish from IS200TTURH1BED and IS200VTURH1B.
- Visual inspection: Check D-sub connectors, terminal blocks, relay seating, transformer mounts, and conformal coating condition.
- Jumper verification: Confirm TMR/Simplex jumper setting matches the existing system configuration.
- Connector continuity check: Test D-sub pin continuity and terminal-block connections with a Fluke 115 or equivalent.
- Relay function test: Energize onboard relays and verify contact closure on each channel.
- Transformer/resistor check: Measure transformer windings and variable resistor ranges against expected values.
- Backplane interface test: Seat the board on a test backplane or with the paired VTUR/PTUR board and verify communication.
- Firmware/logging: Record any board revision labels, serial numbers, and paired processor board revisions.
- ESD packing: Seal in anti-static bag with desiccant and rigid foam.
The Engineer’s Warning (Pitfalls)
- TURH ≠ TTUR. IS200TURH1BED and IS200TTURH1BED are different terminal boards with different signal maps. Swapping them will not work and may damage connected wiring.
- Jumper mismatch causes silent failures. If the TMR/Simplex jumper does not match the system architecture, the board may appear healthy but fail to pass critical trip or speed signals.
- Relay contacts degrade over time. A TURH board can pass visual inspection but still have pitted or oxidized relay contacts that fail under load. Always test relay continuity under supervision.
- Paired board revision matters. The TURH must match the revision and configuration of its paired VTUR or PTUR processor board. Mismatched revisions can cause configuration faults during boot.
Installation & Configuration Guide
1. Pre-Installation ⚠️
- Confirm with operations that the turbine control system can be safely placed in maintenance mode.
- Photograph existing jumper settings, connector wiring, and paired processor board revision.
- Record the system architecture (TMR, Dual, or Simplex) and verify the replacement board jumper matches.
2. Removal
- Place the controller in a safe maintenance state and disable affected trip outputs.
- Disconnect all field wiring from the terminal blocks and D-sub connectors.
- Unseat the TURH board from the backplane carefully.
- Label all connectors and wiring before removal.
3. Installation
- Verify the TMR/Simplex jumper matches the existing system before installing. This prevents most startup failures.
- Inspect the backplane connector for bent pins or contamination.
- Seat the IS200TURH1BED firmly and evenly onto the backplane.
- Reconnect all field wiring to the correct terminals and D-sub connectors.
- Verify the paired VTUR/PTUR board is properly seated and revision-matched.
4. Power-On & Testing
- Apply power and observe the processor board LED sequence.
- Verify communication between the TURH and the paired VTUR/PTUR board.
- Test each relay channel and speed signal path under supervision.
- Confirm trip relay operation and generator sync signal routing.
- Document the board revision, jumper settings, and test results for the maintenance log.
Compatible Replacement Models
| Compatibility | Model / Order Code | Notes |
|---|---|---|
| ✅ Drop-in Replacement | IS200TURH1BED | Exact match. Verify jumper setting and paired board revision. |
| ⚠️ Revised Variant | IS200TURH1BEx (later revision) | Later TURH revision. Confirm jumper compatibility and signal map with GE documentation. |
| ⚠️ Related Terminal Board | IS200TTURH1BED | TTUR terminal board — different signal routing. Not interchangeable with TURH. |
| ⚠️ Paired Processor Board | IS200VTURH1B | VTUR processor board that pairs with TURH. Not a replacement for the terminal board itself. |
| ❌ Not Interchangeable | IS200TREGH1BDC | Regulator terminal board for different I/O functions. Not a TURH substitute. |
| ❌ Not Interchangeable | IS200TSVCH1AED | Servo terminal board. Different application entirely. |
Frequently Asked Questions (FAQ)
Q: Can I hot-swap the IS200TURH1BED while the turbine is running?
Not without a proper maintenance procedure. The TURH routes trip relay signals and speed inputs. Removing it can cause an immediate turbine trip. Always coordinate with operations and place the system in a safe maintenance state first.Q: What is the difference between IS200TURH1BED and IS200TTURH1BED?
TURH is the turbine regulation terminal board that pairs with VTUR/PTUR processor boards. TTUR is a different terminal board with a different signal map. They are not interchangeable. Always verify the exact prefix on the nameplate.Q: What does the TMR/Simplex jumper do?
It configures the board for either Triple Modular Redundant (TMR) or Simplex system architecture. If the jumper does not match the system, the board will not pass signals correctly and the controller will fault.Q: Which processor boards pair with IS200TURH1BED?
It typically pairs with IS200VTURH1B (VTUR) and IS200PTURH1x (PTUR) processor boards in Mark VIe turbine control systems.Q: Why does the controller fault after replacing the TURH board?
Most likely causes are jumper mismatch, incorrect board revision, loose backplane connection, or mismatched paired processor board. Check the jumper setting first.Q: Can I use a refurbished IS200TURH1BED?
Yes, provided it passes relay continuity testing, connector inspection, and jumper verification. Refurbished units are common for legacy Mark VIe components. Always request a test report.Q: Does this board have conformal coating?
Many Mark VIe boards include conformal coating for moisture and chemical resistance. Verify the physical board condition, as coating quality varies between new, surplus, and refurbished units.
