The GE IS200TRPAH2AGD Aeroderivative Turbine Primary Trip Board is a safety-critical terminal board used within GE Industrial Control Systems for aeroderivative turbine protection applications. As a member of the TRPA board family, the IS200TRPAH2AGD Aeroderivative Turbine Primary Trip Board provides the primary trip function for aeroderivative turbines, accepting speed inputs from passive magnetic or active TTL pulse rate devices, monitoring trip string voltages, providing a fail-safe emergency stop input, and driving two TMR-voted trip contact outputs to the main breaker trip coil.
The IS200TRPAH2AGD Aeroderivative Turbine Primary Trip Board is identified by the GE part numbering convention used throughout the Industrial Control Systems product line. The "IS200" prefix identifies the board as a GE Industrial Control Systems product, with "200" specifically indicating that the board is a base-level assembly. The "TRPA" acronym identifies the board's functional designation as an Aeroderivative Turbine Primary Trip Board. The "H2" designation identifies the hardware group and the 125 V DC output contact rating variant, while the "AGD" suffix identifies the artwork and functional revision combination. All digits are important when ordering or replacing any board, as boards of different revision levels may not contain identical hardware, and GE ensures backward compatibility of replacement boards while noting that different revision levels may not contain identical components.
The IS200TRPAH2AGD Aeroderivative Turbine Primary Trip Board is the H2A version of the TRPA family, providing 125 V DC output contact ratings. The TRPA family also includes the H1A version with 24 V DC output contact ratings, and the S1A and S2A safety-certified versions that are IEC 61508 certified with the YTUR I/O pack. The board is compatible with the Mark VIe control system using the IS220PTUR I/O pack, but is not compatible with the Mark VIeS Safety control using the IS200YTUR I/O pack, as the H1A and H2A versions are not safety certified. The H2A version is intended for applications that require 125 V DC trip coil and trip string voltages, which are common in larger aeroderivative turbine installations.
This product introduction provides detailed technical information, functional descriptions, connector assignments, configuration guidance, and comprehensive specifications for the GE IS200TRPAH2AGD Aeroderivative Turbine Primary Trip Board, serving as an essential reference for control system engineers, maintenance technicians, and system integrators working with GE industrial control equipment.
Functional Architecture and Signal Processing
The IS200TRPAH2AGD Aeroderivative Turbine Primary Trip Board is built around a robust triple modular redundant (TMR) architecture that provides the primary trip function for the aeroderivative turbine. The board performs several distinct functions that together ensure reliable and safe turbine protection, including speed sensing, trip string voltage monitoring, emergency stop handling, and TMR-voted trip relay output.
The board accepts twelve passive pulse rate devices, four per R, S, and T section, sensing a toothed wheel to measure the turbine speed, or alternatively six active pulse rate inputs, two per TMR section. This speed measurement capability allows the board to detect overspeed conditions and to initiate the primary trip function when the turbine speed exceeds the safe operating limit. The speed inputs are configured using jumpers JP1 and JP2, which select the fanning of the R section pulse rate pickups to the S and T I/O packs, providing flexibility in the speed input wiring arrangement.
The board provides two 24 V DC (H1A) or 125 V DC (H2A) TMR-voted output contacts to the main breaker coil for the trip coil. The trip relays are made using sets of six individual form A devices arranged in a voting pattern, so that any two controllers that vote to close will establish a conduction path through the set. Because detection of a shorted relay is important to preserve tripping reliability, there is a sensing circuit applied to each of the sets of relays. When the relays are commanded to open and voltage is present across the relays, the circuit will detect if one or more relays are shorted, and this signal goes to the I/O pack to create an alarm. The sensing circuit uses the relay commands from all three packs to avoid a false indication in the event that one I/O pack votes to close the relay while the other two I/O packs vote to open.
The board includes four 24–125 V DC voltage detection circuits for monitoring the trip string. Because the trip string circuit is not fixed, there are four general-purpose isolated voltage sensor inputs on the TRPA that can be used to monitor any points in the trip system and drive the voltage status into the system controller where action can be taken. Typical use of these inputs may be to sense the power supply voltage for the two trip strings and to sense the solenoid voltage of the device being driven by the relays.
The board includes one 24–125 V DC fail-safe emergency stop input for removing power from the trip relays. The emergency stop function consists of an optically isolated input circuit designed for a DC input in the range of 24 V to 125 V nominal. When energized, the circuit enables coil drive power in the R, S, and T relay circuits through independent hardware paths. The response time of this circuit is less than five milliseconds, and combined with the response time of the trip relays of less than one millisecond, this yields a very fast emergency stop response. The emergency stop is monitored by the I/O pack, but the action to remove trip relay coil power is entirely in the hardware of the TRPA, providing a hardware-based safety function that does not depend on software.
System Design and Operating Modes
The IS200TRPAH2AGD Aeroderivative Turbine Primary Trip Board is designed for application in two different system configurations, providing flexibility in the turbine protection architecture.
In the first configuration, a TTUR terminal board is used to hold three I/O packs, and the TRPA terminal board may be connected using three cables with DC-37 pin connectors on each end. In this mode of operation, the TRPA provides two contact-voted trip relay outputs, emergency stop, and four voltage sensors, while the TTUR provides the normal set of features described for that board, including speed inputs, synchronizing relays, and bus and generator voltage feedbacks. The TRPA speed inputs are not active and should not be connected with this board arrangement, so the speed measurement function is provided by the TTUR board rather than the TRPA.
In the second configuration, the TRPA board can be used with three I/O packs mounted directly to it. In this mode of operation, the speed inputs to the TRPA become active paths into the I/O pack, allowing for a single terminal board primary trip solution. Simplex operation is not possible in this configuration, because the TMR architecture requires all three I/O packs to be present for the voting and redundancy functions to operate correctly.
The speed inputs of the IS200TRPAH2AGD Aeroderivative Turbine Primary Trip Board provide two options when used with I/O packs mounted directly on the TRPA. Each I/O pack can receive a dedicated set of four speed inputs from its respective TRPA terminal points, as is done on the TTUR. Alternatively, jumpers P1 and P2 can be placed on the TRPA to take the first four speed inputs, those for the R pack, and fan them to the S and T packs. When this option is selected, the terminal board points for the S and T speed inputs become no-connects and should not be used.
The jumper configuration table for the speed input connections defines several possible arrangements. When wiring to all twelve pulse inputs, PR1_R through PR4_T, each set of four pulse inputs goes to its own dedicated I/O pack, and the jumpers cannot be used and must be placed in the STORE position. When wiring to the TTL pulse inputs, TTL1_R through TTL2_T, each set of two pulse inputs goes to its own dedicated I/O pack, and the jumpers cannot be used and must be placed in the STORE position. When wiring to the bottom four pulse inputs only, PR1_R through PR4_R, with no wiring to TTL1_R through TTL2_T or PR1_S through PR4_T, the same set of signals is fanned to all the I/O packs, and the jumper should be placed over the pin pairs. When wiring to the bottom two pulse inputs, TTL1_R through TTL2_R, the TTL signals cannot be fanned, and only the R I/O pack will receive data, so the jumper cannot be used and must be placed in the STORE position.
The contact outputs of the IS200TRPAH2AGD Aeroderivative Turbine Primary Trip Board are polarity sensitive, so the circuit must be wired carefully to avoid damaging the relays. There is no contact or solenoid suppression on the board, and the user must add external solenoid suppression to avoid damaging the relays and their contacts. The board's contact outputs are rated for NEMA class F, with a minimum of 100,000 operations.
The emergency stop and trip input must be powered for the relays to operate. If the user does not need or use an emergency stop, then the local trip power source, P24O and P24R, should be jumpered to the respective trip inputs at the terminal board. The emergency stop must be connected to a clean DC source, either a battery or a filtered rectified AC source with less than 5% ripple. There must be a minimum of 18 V DC at the trip inputs for proper operation. The current required is kept low to minimize the drop on long cable runs. Because the trip input is very fast, less than 5 milliseconds, and the output relay contacts are also fast, less than 15 milliseconds, best wiring practices should be utilized to avoid misoperation, using twisted-pair cable when possible and avoiding running with AC wiring.
The emergency stop signal that is reported in the ToolboxST E-Stop Tab is latched by firmware and needs a Master Reset to clear that status. A true indicates a completed emergency stop circuit, while a false indicates a loss of the emergency stop since the last Master Reset, not the current state of the emergency stop circuit.
Installation and Wiring
The IS200TRPAH2AGD Aeroderivative Turbine Primary Trip Board is designed for straightforward installation and field wiring. TTL pulse rate pickups, voltage detection, emergency stop, and the breaker relay are wired to the I/O terminal block TB1, while passive pulse rate pickups are wired to TB2. Each block is held down with two screws and has 24 terminals accepting up to #12 AWG wires, and a shield termination strip attached to chassis ground is located immediately to the left of each terminal block, ensuring proper shielding and grounding of the field wiring.
In 240 V AC applications, it is important not to inadvertently cross-connect the 240 V AC and the DC voltages, because the peak voltage will exceed the Transorb rating and result in a failure. Most AC supplies operate with a grounded neutral, and if an inadvertent connection between the 125 V DC and the AC voltage is created, the sum of the AC peak voltage and the 125 V DC is applied to the Transorb connected between DC and ground. However, in 120 V AC applications, the Transorb rating can withstand the peak voltage without causing a failure.
The board size is 33.0 cm high by 17.8 cm wide (13 in x 7 in), and the terminal blocks can be unplugged from the terminal board for maintenance. The board includes a DC-62 pin type connector for the I/O packs, and the DC-37 pin connectors with latching fasteners for the cables to JR4, JS4, and JT4 to the TTUR, for just trip contacts, emergency stop, and voltage sensing circuits.
Diagnostics and Fault Detection
The IS200TRPAH2AGD Aeroderivative Turbine Primary Trip Board provides comprehensive diagnostic capabilities that assist with system verification and fault isolation. Feedback from the shorted contact detector is checked, and if there is a problem with the control signal an alarm should be created. Feedback from the emergency stop and trip input is checked, and if there is a problem with the signal a fault should be created. Feedback from the speed pickup fanning jumpers is checked, and if there is a mismatch between intention and actual position, an alarm should be created.
If any one of these signals goes unhealthy, a composite diagnostic alarm occurs, and the diagnostic signals can be individually latched and then reset with the RESET_DIA signal if they go healthy. The terminal board connectors have their own ID device that is interrogated by the I/O pack, with the ID device being a read-only chip coded with the terminal board serial number, board type, revision number, and plug location. When the chip is read by the I/O pack and a mismatch is encountered, a hardware incompatibility fault is created, preventing the system from operating with incorrect or mismatched hardware.
Configuration
The IS200TRPAH2AGD Aeroderivative Turbine Primary Trip Board is configured using jumpers JP1 and JP2, which select the fanning of the four R section passive speed pickups to the S and T section I/O packs. Placing the jumper over the pin pairs fans the four R speed inputs to the other two TMR sections, while leaving the jumpers in the STORE position preserves the dedicated speed inputs for each section. The configuration must be verified against the system wiring and the intended operating mode to ensure correct operation of the speed measurement and trip functions.
Application Suitability and System Integration
The IS200TRPAH2AGD Aeroderivative Turbine Primary Trip Board is a critical component of the aeroderivative turbine protection system, providing the primary trip function that protects the turbine from overspeed conditions and other hazardous events. The board's TMR architecture, with three I/O packs and voting on the trip relay outputs, provides the fault tolerance and high availability required for a safety-critical protection function.
The board's speed measurement capability, with twelve passive pulse rate devices or six active TTL pulse rate inputs, allows the turbine speed to be measured redundantly across the three TMR sections, ensuring that an overspeed condition is detected even if one speed sensor fails. The board's four voltage detection circuits allow the trip string voltages to be monitored at multiple points, providing diagnostic visibility into the health of the trip system. The board's hardware-based emergency stop function provides a fast and reliable means of removing power from the trip relays, independent of the software and the I/O packs.
In the TTUR-based configuration, the TRPA provides the trip relay outputs, emergency stop, and voltage sensors, while the TTUR provides the speed inputs and the synchronizing and voltage feedback functions. In the direct-mounted configuration, the TRPA provides the complete primary trip solution, with the speed inputs, trip relay outputs, emergency stop, and voltage sensors all integrated into a single terminal board.
The board's contact outputs are polarity sensitive, and the user must add external solenoid suppression to protect the relays and their contacts. The emergency stop input must be connected to a clean DC source, and the wiring should follow best practices to avoid misoperation of the fast trip input and output relay circuits.
Maintenance and Lifecycle
The IS200TRPAH2AGD Aeroderivative Turbine Primary Trip Board is designed for long service life with minimal maintenance. The board contains the trip relays as its only moving parts, and its robust construction and surface-mount technology ensure high reliability in continuous industrial operation. Routine maintenance consists of periodic visual inspection of the board, terminal blocks, and wiring, verification that the trip string voltages are within specification, and confirmation that the shield terminals are properly connected.
The board's diagnostic features, including the shorted contact detector feedback, the emergency stop input feedback, the speed pickup fanning jumper feedback, and the onboard ID chip, simplify troubleshooting and ensure that the correct board is installed in each location. If the shorted contact detector identifies a shorted relay, an alarm is created, alerting the maintenance technician to a potential loss of tripping reliability. If the emergency stop input feedback indicates a problem, a fault is created, alerting the operator to a potential loss of the emergency stop function.
If the board requires replacement, the process is straightforward. After de-energizing the associated equipment and verifying that no power exists, the pluggable terminal blocks should be labeled and removed, and the board should be removed from its mounting. The replacement board should be installed in the same position, the JP1 and JP2 jumpers set to match the original configuration, and the terminal blocks reconnected as labeled before returning the system to service.
GE Industrial Control Systems ensures compatibility of its replacement boards, even though boards of different revision levels may not contain identical hardware. When ordering a replacement IS200TRPAH2AGD Aeroderivative Turbine Primary Trip Board, provide the complete part number and description, the drive or system serial number, and the Material List (ML) number. The factory may substitute later versions based on availability and design enhancements, but backward compatibility of replacement boards is guaranteed.
Conclusion
The GE IS200TRPAH2AGD Aeroderivative Turbine Primary Trip Board is a reliable, robust, and safety-critical protection module for GE Industrial Control Systems aeroderivative turbine applications. Its twelve passive or six active speed inputs, its two TMR-voted trip contact outputs with 125 V DC rating, its four isolated voltage detection circuits, its hardware-based emergency stop function, and its comprehensive diagnostics provide the speed measurement, trip output, voltage monitoring, and emergency stop functionality required for the primary trip function.
With its pluggable terminal blocks, clearly labeled connectors, comprehensive diagnostics, and support for both TTUR-based and direct-mounted system configurations, the IS200TRPAH2AGD Aeroderivative Turbine Primary Trip Board is designed for easy installation, verification, and maintenance. Backed by GE's quality manufacturing, global support network, and commitment to backward compatibility, the IS200TRPAH2AGD Aeroderivative Turbine Primary Trip Board continues to deliver the performance, durability, and safety that industrial users expect from GE. Whether used in a new installation or as a replacement for an existing board, the IS200TRPAH2AGD Aeroderivative Turbine Primary Trip Board provides the primary trip functionality required for reliable and safe aeroderivative turbine operation.
