IS200TREGH1AAA - Turbine Emergency Trip Terminal Board

SPECIFICATIONS:

Part Number: IS200TREGH1AAA
Manufacturer: General Electric
Series: Mark VI
Product Type: Emergency Trip Terminal Board
Number of Trip Solenoids: 3
Relay Outputs: 3
Connectors: JX1, JY1, JZ1
Operating Voltage Range: 18–30 V DC
Operating Temperature: 0 deg C to 60 deg C
Trip Inputs: 125/24 V DC
Solenoid Response Time: 0.1 sec
Size: 17.8 cm wide x 33.02 cm
Repair: 3-7 Days
Country of Origin: USA
Availability: In Stock
Manual: GEH-6421l

FUNCTIONAL DESCRIPTION:

IS200TREGH1AAA is a Turbine Emergency Trip Terminal Board manufactured and designed by General Electric as part of the Mark VI Series used in GE Speedtronic Gas Turbine Control Systems. The TREG board supplies DC power to up to three emergency trip solenoids and is managed by the I/O controller. These solenoids are connected between the TREG and TRPG terminal boards, with TREG providing the positive DC power and TRPG supplying the return (negative) side. The I/O controller is responsible for emergency overspeed protection and emergency stop functions. It also controls 12 relays on the TREG board—nine of which are organized into three groups of three relays. These groups implement a voting logic to control the three trip solenoids. There are multiple types of TREG boards available, each designed for specific applications.

• H1B: The H1B is the primary version used in 125 V DC applications and replaces the older H1A version in new production. It generates redundant power by combining inputs from the JX1, JY1, and JZ1 connectors through diode isolation. This power feeds the economizing relays and status feedback circuits, while the trip relay circuits maintain power isolation.

• H2B: Designed for 24 V DC applications, the H2B shares all functional characteristics with the H1B, apart from the operating voltage.

• H3B: A variant of H1B, the H3B is used in systems with redundant TREG boards. In this version, only the JX1 connector provides power to the feedback and economizing relay circuits.

• H4B: Another modified form of the H1B, the H4B is also used in redundant TREG configurations, with the JY1 connector as the sole power source for the feedback and economizing relay circuits.

• H5B: Similar to H3B and H4B, the H5B is designed for redundant TREG systems. In this version, the JZ1 connector exclusively supplies power to the feedback and economizing relay circuits.

Typically, one H3B and one H4B board are used in tandem in redundant TREG applications. To preserve the control power separation built into these systems, system repairs must be carried out using the appropriate type of board.

INSTALLATION:

• The three emergency trip solenoids, along with their associated economizing resistors and the emergency stop (E-Stop) circuit, are directly connected to the first I/O terminal block on the TREG board. This configuration ensures a reliable and immediate response path for critical trip functions, enabling fast shutdown of the turbine during emergency conditions.

• The economizing resistors are integrated to reduce power consumption and heat generation once the solenoids have been activated, maintaining the solenoids in their energized state with minimal current draw.

• The second I/O terminal block is designed to accommodate up to seven trip interlock inputs. These interlocks are typically sourced from various protective and permissive signals across the turbine control system, such as low lube oil pressure, high vibration, thrust bearing wear, or fire protection systems. Each interlock input serves as a safety layer, ensuring that the turbine trips automatically if unsafe conditions are detected.

• This dual-terminal block arrangement allows for organized, scalable wiring while maintaining a clear separation between direct trip actuation components and interlock logic signals. It also supports ease of troubleshooting, system expansion, and future upgrades.

OPERATION:

The TREG board is fully controlled by the I/O controller. Its only connections to the control modules are via the J2 power cable and the trip solenoid circuits. In simplex systems, an additional cable from the J1 connector is used to transmit a trip signal to the TSVO terminal board. This signal activates the servo valve clamp function, ensuring the servo valves are securely held in a safe position during a turbine trip event.

CONTROL OF TRIP SOLENOIDS:

Both TRPG and TREG control the trip solenoids so that either one can remove power and actuate the hydraulics to close the steam or fuel valves. The nine trip relay coils on TREG are supplied with 28 V dc from the I/O controller. The trip solenoids are supplied with 125 V dc through plug J2, and draw up to 1 A with a 0.1-second L/R time constant.

A separately fused 125 V dc feeder is provided from the turbine control for the solenoids, which energize in the run mode and de-energize in the trip mode. Diagnostics monitor each 125 V dc feeder from the power distribution module at its point of entry on the terminal board to verify the fuse integrity and the cable connection.

Two series contacts from each emergency trip relay (ETR1, 2, 3) are connected to the positive 125 V dc feeder for each solenoid, and two series contacts from each primary trip relay (PTR1,2,3 in TRPG) are connected to the negative 125 V dc feeder for each solenoid. An economizing relay (KE1, 2, 3) is supplied for each solenoid with a normally closed contact in parallel with the current limiting resistor. These relays are used to reduce the current load after the solenoids are energized. The ETR and KE relay coils are powered from a 28 V dc source from the I/O controller. Each I/O controller in each of the R8, S8, and T8 sections supplies an independent 28 V dc source.

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FREQUENTLY ASKED QUESTIONS:

How are the trip solenoids wired within the system?

Trip solenoids, economizing resistors, and the emergency stop (E-Stop) circuit are directly connected to the first I/O terminal block. This block carries the high-priority trip signal paths. Up to seven trip interlocks are connected to the second terminal block for safety and permissive conditions.

How are connectors JX1, JY1, and JZ1 identified and verified by the I/O controller?

Each connector on the TREG board has its ID device, containing essential information such as the terminal board serial number, board type, revision number, and plug location. The I/O controller interrogates these ID devices, and if a mismatch is detected, a hardware incompatibility fault is generated.

What diagnostics does the I/O controller perform on the board and connected devices?

The I/O controller conducts diagnostics covering various aspects, including trip relay driver and contact feedback, solenoid voltage, economizer relay driver and contact feedback, K25A relay driver and coil, servo clamp relay driver and contact feedback, and solenoid voltage source.