GE IS200TREGH1B TREG Terminal Board

The IS200TREGH1B (Turbine Emergency Trip) terminal board is a critical safety protection component in GE’s Mark VI and Mark Vle turbine control systems. Designed specifically to supply power to three emergency trip solenoids and to be precisely controlled by the I/O controller, it ensures rapid and reliable shutdown of fuel or steam valves in emergency situations, thereby safeguarding turbine unit operation. The IS200TREGH1B terminal board works in conjunction with the TRPG terminal board to form a complete trip protection circuit: TREG supplies the positive side of the DC power to the solenoids, while TRPG supplies the negative side.

As a core hardware element of the turbine protection system, TREG not only provides highly reliable power management and signal voting mechanisms but also supports redundant configurations and comprehensive online diagnostics. It is suitable for emergency protection scenarios in various industrial gas turbine applications.

2. Functional Description

2.1 Main Functions

• Emergency Trip Control: Supplies 125 V DC (or 24 V DC) power to three trip solenoids and implements “two-out-of-three” or “three-out-of-three” voting logic through multiple relays to ensure high reliability of trip signals.

• Redundant Power Design: Diode-OR combination of control power from connectors JX1, JY1, and JZ1 provides redundant power for status feedback circuits and economizing relays, while maintaining power separation for trip relay circuits.

• System Integration: Works closely with the VPRO (turbine protection module) or PPRO (I/O pack on SPRO) to achieve efficient communication and coordination with the control system.

• Diagnostics and Monitoring: Supports real-time diagnostics of solenoid power, relay drivers, contact feedback, and power integrity to ensure system status is controllable and verifiable.

2.2 Board Types and Versions

TREG terminal boards are available in multiple versions depending on voltage level and redundancy requirements:

In redundant systems, it is typical to combine an H3B board with an H4B (or H5B) board to ensure physical separation of control power and enhance system reliability. During maintenance, the same board type must be used to preserve the designed power isolation.

3. System Integration and Configuration

3.1 Integration with Mark VI Systems

In Mark VI systems, IS200TREGH1B is connected to the VPRO module via cables with molded plugs. The VPRO, as the turbine protection module, handles trip logic, overspeed protection, and emergency stop functions, and communicates with the control system via IONet. The 12 relays on TREG are controlled by VPRO, with nine of them grouped into three sets of three to implement input voting for the three trip solenoids.

3.2 Integration with Mark Vle Systems

In Mark Vle systems, IS200TREGH1B is controlled by the PPRO I/O pack on SPRO. The PPRO pack plugs into the D-type connectors on SPRO, and TREG is connected to the SPRO board via molded-plug cables to acquire and execute trip signals.

3.3 Hardware Configuration

The IS200TREGH1B terminal board itself has no software-configurable switches; all functional settings are implemented via hardware jumpers:

• JPAL Jumper: Selects current input or voltage input mode.

• JPBJ Jumper: Selects whether the return signal is grounded or left open.

• Terminals 15–17 Jumper: Must be installed if the second emergency stop input is not required.

Other advanced configurations (such as logic configuration and test functions) are performed via the Toolbox software in VPRO or PPRO.

4. Installation and Wiring

4.1 Physical Installation

The IS200TREGH1B terminal board adopts a modular design with pluggable barrier-type terminal blocks for easy removal during maintenance. It is equipped with 37-pin D-shell connectors with latching fasteners to ensure reliable cable connections. A shield bar is included for effective EMI suppression.

4.2 Wiring Description

• First Terminal Block: Directly connects the three trip solenoids, economizing resistors, and the emergency stop pushbutton.

• Second Terminal Block: Can connect up to seven trip interlock signals.

• Power Connections: Connector J2 supplies 125 V DC (or 24 V DC) power to the solenoids; JX1, JY1, and JZ1 receive 28 V DC control power from the R8, S8, and T8 protection module sections, respectively.

• Signal Feedback: Solenoid status is fed back to the I/O controller via contact feedback loops for closed-loop monitoring.

All termination points support up to two #12 AWG wires with 300 V insulation, meeting safety requirements for industrial environments.

5. Operating Principle and Control Logic

5.1 Trip Solenoid Control

IS200TREGH1B and TRPG together control the trip solenoids; either can cut off power and actuate the hydraulic system to close the valves. The solenoids are energized during run mode and de‑energized during trip mode. Each solenoid circuit includes a metal oxide varistor (MOV) for current suppression and a 10 Ω, 70 W economizing resistor to reduce steady‑state current.

5.2 Relay Logic

• Emergency Trip Relays (ETR1–ETR3): Two series contacts per relay connect to the positive 125 V DC feeder.

• Primary Trip Relays (PTR1–PTR3, located in TRPG): Connect to the negative 125 V DC feeder.

• Economizing Relays (KE1–KE3): Close after a delay to shunt the current‑limiting resistor, reducing power consumption.

• Master Trip Relays (K4X, K4Y, K4Z): Disconnect the 28 V DC bus from the ETR and KE relay coils in the event of a manual emergency trip.

5.3 Servo Clamp Function (Simplex Only)

In simplex configurations, the K4CL servo clamp relay energizes upon a trip and sends a contact feedback directly to the TSVO servo terminal board, which disconnects the servo current source and applies a bias to drive the control valve closed. This prevents the valve from opening erroneously due to servo amplifier failure.

5.4 Independence of Overspeed Protection

The primary and emergency overspeed protection systems operate independently of the TREG circuit and can trip the hydraulic trip solenoids directly, providing multiple layers of protection.

6. Testing and Diagnostic Features

6.1 Online Testing

Using application software in the controller, each trip solenoid can be manually tripped one at a time. Testing can be performed via the PTR relays from the controller or via the ETR relays from the protection module, with contact feedback from each solenoid providing positive trip confirmation.

6.2 Offline Overspeed Testing

Supports primary and emergency overspeed offline tests by simulating overspeed conditions in software to verify correct trip response.

6.3 Comprehensive Diagnostics

The I/O controller performs continuous diagnostics on TREG and connected devices, covering:

• Trip relay drivers and contact feedback

• Solenoid voltage monitoring

• Economizing relay drivers and contact feedback

• K25A relay driver and coil

• Servo clamp relay driver and contact feedback

• Solenoid power supply status

6.4 Hardware Identification and Compatibility

Connectors JX1, JY1, and JZ1 each contain a read‑only ID chip storing the board serial number, type, revision, and slot location. The I/O controller reads this information and performs verification; a mismatch triggers a hardware incompatibility fault to prevent system failure due to incorrect assembly.

7. Product Advantages and Application Scenarios

7.1 Core Advantages

• High Reliability: Triple‑redundant voting logic avoids spurious trips or failures due to single‑point faults.

• Flexible Configuration: Supports both 125 V DC and 24 V DC voltage levels to adapt to different industrial standards.

• Redundant Design: Multiple versions enable physical separation of power and signal paths, enhancing system availability.

• Intelligent Diagnostics: Comprehensive hardware self‑diagnostics and ID recognition facilitate maintenance and fault localization.

• Easy Maintenance: Pluggable terminal blocks and modular structure support online replacement and quick servicing.

7.2 Applicable Fields

• Gas turbine power plants

• Combined‑cycle power stations

• Industrial drive turbine units

• Offshore platform power generation systems

• Other rotating machinery systems requiring high‑reliability emergency shutdown protection