The GE IS200TPROH1CBB Emergency Protection Terminal Board is a specialized protection and signal interface terminal board used within GE Industrial Control Systems. As a member of the TPRO board family, the IS200TPROH1CBB Emergency Protection Terminal Board provides the VPRO with speed signals, temperature signals, generator voltage, and bus voltage as part of an independent emergency overspeed and synchronization protection system. The protection system consists of triple redundant VPRO boards in a module separate from the turbine control system, controlling the trip solenoids through the TREx boards (TREG, TREL, or TRES), and the TPRO supplies inputs to all three VPRO boards.
The IS200TPROH1CBB Emergency Protection Terminal 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 "TPRO" acronym identifies the board's functional designation as an Emergency Protection Terminal Board. The "H1" designation identifies the hardware group, while the "CBB" 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 VPRO board provides the emergency trip function, and up to three trip solenoids can be connected between the TREx and TRPx terminal boards. TREx provides the positive side of the 125 V DC to the solenoids, and TRPx provides the negative side, so either board can trip the turbine. VPRO provides emergency overspeed protection and the emergency stop functions, and it controls the 12 relays on TREG, nine of which form three groups of three to vote inputs controlling the three trip solenoids. A second TREG board may be driven from VPRO through J4, providing additional redundancy for the trip function. It is important to note that the TPRO does not work with the Mark VIe I/O packs, so the IS200TPROH1CBB Emergency Protection Terminal Board is intended for use with the VPRO boards in the dedicated protection module.
This product introduction provides detailed technical information, functional descriptions, connector assignments, configuration guidance, and comprehensive specifications for the GE IS200TPROH1CBB Emergency Protection Terminal 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 IS200TPROH1CBB Emergency Protection Terminal Board is built around a robust signal interface architecture that provides the VPRO boards with the speed, temperature, generator voltage, and bus voltage signals required for emergency overspeed protection and backup synchronization check protection. The board performs several distinct functions that ensure reliable and accurate signal acquisition for the protection system, which operates independently of the main turbine control system to provide a diverse and redundant protection layer.
The main purpose of the IS200TPROH1CBB Emergency Protection Terminal Board is to supply speed signals to the VPRO for the emergency overspeed protection of the turbine. Speed control and overspeed protection are implemented with six passive magnetic speed pickups. The first three are monitored by the controller, which uses the median signal for speed control and the primary overspeed protection, while the second three are separately connected to the three VPROs in the protection module. Provision is made for nine passive magnetic speed pickups or active pulse rate transducers of the TTL type on the TPRO terminal board, with three being monitored by each of the three VPROs. This arrangement provides redundant speed measurement for the emergency overspeed protection function, ensuring that a failure in one speed pickup or one VPRO does not compromise the protection system.
In addition to the speed signals, the IS200TPROH1CBB Emergency Protection Terminal Board supplies generator signals for backup synchronization check protection, three analog current inputs, and nine thermocouple inputs, primarily for exhaust over-temperature protection on gas turbines. The VPRO provides 28 V DC to the TPRO to power the three analog input transmitters, eliminating the need for separate field power supplies for these transmitters.
Speed Control and Overspeed Protection
The speed control and overspeed protection function of the IS200TPROH1CBB Emergency Protection Terminal Board is implemented with passive magnetic speed pickups that generate a signal proportional to the turbine speed. The magnetic pickup output has an output resistance of 200 ohms with an inductance of 85 mH, and generates 150 V peak-to-peak into 60 kilohms at the TPRO terminal block, with insufficient energy for a spark. The maximum short circuit current is approximately 100 mA, and the system applies up to 400 ohm normal mode load to the input signal to reduce the voltage at the terminals.
The magnetic pickup sensors can be up to 300 meters (984 feet) from the cabinet, assuming that shielded pair cable is used, with typical 70 nF single-ended or 35 nF differential capacitance and 15 ohms resistance. The MPU pulse rate range is 2 Hz to 20 kHz, and the MPU input circuit sensitivity has a minimum signal of 27 mV peak at 2 Hz and a minimum signal of 450 mV peak at 14 kHz, ensuring reliable speed measurement across the full operating range of the turbine.
Backup Synchronization Check Protection
The IS200TPROH1CBB Emergency Protection Terminal Board provides inputs to the protection module for backup synchronization check protection. The generator and bus voltages are supplied from two single-phase potential transformers with a secondary output supplying a nominal 115 V RMS. The maximum cable length between the potential transformers and the turbine control is 100 meters of 18 AWG twisted, shielded wire, and each potential transformer is magnetically isolated with a 1,500 V RMS rated barrier and a circuit load of less than 3 VA.
Each potential transformer input is internally connected in parallel through the TPRO to the three VPROs in the protection module. The triple redundant phase slip windows result in a voted logical output on the TREG terminal board, which drives the K25A relay. This relay's contacts are connected in series with the synch permissive relay (K25P) and the auto synch relay (K25) to ensure that no false command is issued to close the generator breaker. Similarly, contacts from the K25A contact are connected in series with the contacts from remote, manual synchronizing equipment to ensure no false commands, providing a comprehensive and reliable synchronization check protection function.
The generator and bus voltage measurement accuracy is 0.5% of rated volts RMS, the frequency accuracy is 0.05%, and the phase difference measurement is better than 1 degree. The allowable voltage range for synchronizing is 75 to 130 V RMS, and each input has a load of less than 3 VA.
The IS200TPROH1CBB Emergency Protection Terminal Board provides thermocouple and analog inputs to the protection module, primarily for gas turbine applications. Nine thermocouple inputs are monitored, with three connected to each VPRO, and these are generally used for backup exhaust over-temperature protection. The thermocouple inputs have the same specifications as the VTCC board, ensuring consistent measurement performance across the GE control system family.
In addition to the thermocouple inputs, the IS200TPROH1CBB Emergency Protection Terminal Board provides one input that can be configured for ±5 V DC, ±10 V DC, or 4–20 mA, and two inputs that are 4–20 mA current inputs. These analog inputs are connected to the TPRO terminal board and feed the inputs in parallel to the three VPROs, providing the protection module with the analog signals required for its protection functions. The analog inputs have the same specifications as the VAIC board, and the analog sensors are powered by the 28 V DC supply from the VPRO.
Installation and Wiring
The IS200TPROH1CBB Emergency Protection Terminal Board is designed for straightforward installation and field wiring. The generator and bus potential transformers, analog inputs, and thermocouples are wired to the first terminal block on the TPRO, while the magnetic speed pickups are wired to the second block. Jumpers JP1A and JP1B are set to give either a 4–20 mA or voltage input on the first of the three analog inputs, allowing the board to be adapted to the specific analog input requirements of the application.
The wiring connections are shown in the TPRO wiring and cabling diagram, with two cables going to each of the three VPRO boards. The terminal blocks can be unplugged from the terminal board for maintenance, and up to two #12 AWG wires per point with 300 volt insulation can be accommodated, providing flexibility for different field wiring requirements. The board size is 17.8 cm wide by 33.02 cm high (7.0 in x 13 in), and the shield bar provides a termination point for the cable shields, ensuring proper shielding and grounding of the field wiring.
Diagnostics and Fault Detection
The IS200TPROH1CBB Emergency Protection Terminal Board provides comprehensive diagnostic capabilities that assist with system verification and fault isolation. The VPRO makes diagnostic checks on the TPRO and its cables and input signals, and if high or low limits on analog inputs are exceeded, a fault is created. If any one of the signals goes unhealthy, a composite diagnostic alarm L3DIAG_VPROR (or S, or T) occurs. The diagnostic signals can be individually latched and then reset with the RESET_DIA signal if they go healthy, providing flexible diagnostic management for the maintenance technician.
The terminal board connectors on the TPRO have their own ID device that is interrogated by the I/O board. The ID device is 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 VPRO and a mismatch is encountered, a hardware incompatibility fault is created, preventing the system from operating with incorrect or mismatched hardware. This diagnostic feature ensures that the correct terminal board is installed in each location and that the system configuration matches the physical hardware.
Application Suitability and System Integration
The IS200TPROH1CBB Emergency Protection Terminal Board is a critical component of the independent emergency overspeed and synchronization protection system used in GE turbine control applications. Its ability to supply speed signals, temperature signals, generator voltage, and bus voltage to the triple redundant VPRO boards provides the protection system with the diverse and redundant inputs required to detect overspeed conditions and to verify synchronization before closing the generator breaker.
In gas turbine protection schemes, the VTUR and VPRO boards share the protection function, with both detecting turbine overspeed and either one able to independently trip the turbine using the relays on the TRPG or TREG boards. The IS200TPROH1CBB Emergency Protection Terminal Board provides the speed signals from the magnetic speed pickups to the VPRO boards, and also provides the generator and bus voltage signals for the backup synchronization check protection, the thermocouple inputs for the backup exhaust over-temperature protection, and the analog inputs for the protection module's other protection functions.
The board's triple redundant architecture, with the inputs fanned out in parallel to the three VPRO boards, ensures that a failure in one VPRO board does not compromise the protection function. The board's support for up to nine passive magnetic speed pickups, with three being monitored by each of the three VPROs, provides redundant speed measurement, and the triple redundant phase slip windows result in a voted logical output on the TREG terminal board, which drives the K25A relay, ensuring that no false command is issued to close the generator breaker.
The board's diagnostic capabilities, including the analog limit checking, the composite diagnostic alarm, and the onboard ID chip, simplify troubleshooting and ensure that the correct board is installed in each location. The diagnostic signals can be individually latched and reset with the RESET_DIA signal if they go healthy, providing flexible diagnostic management for the maintenance technician.
Maintenance and Lifecycle
The IS200TPROH1CBB Emergency Protection Terminal Board is designed for long service life with minimal maintenance. The board contains no moving parts, and its robust construction ensures high reliability in continuous industrial operation. Routine maintenance consists of periodic visual inspection of the board, terminal blocks, and wiring, verification that the analog input limits are within specification, and confirmation that the shield terminals are properly connected.
The board's diagnostic features, including the analog limit checking, the composite diagnostic alarm, and the onboard ID chip, simplify troubleshooting and ensure that the correct board is installed in each location. If an analog input goes outside its high or low limits, a fault is created, and if any signal goes unhealthy, a composite diagnostic alarm occurs. The diagnostic signals can be individually latched and reset with the RESET_DIA signal if they go healthy.
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 jumpers JP1A and JP1B 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 IS200TPROH1CBB Emergency Protection Terminal 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 IS200TPROH1CBB Emergency Protection Terminal Board is a reliable, robust, and critical signal interface for GE Industrial Control Systems emergency protection applications. Its nine passive proximity probes for speed pickups, its generator and bus voltage inputs for backup synchronization check protection, its nine thermocouple inputs for backup exhaust over-temperature protection, and its three analog inputs provide the VPRO boards with the diverse and redundant signals required for the independent emergency overspeed and synchronization protection system.
With its pluggable terminal blocks, clearly labeled connectors, comprehensive diagnostics, and triple redundant architecture, the IS200TPROH1CBB Emergency Protection Terminal Board is designed for easy installation, verification, and maintenance. Backed by GE's quality manufacturing, global support network, and commitment to backward compatibility, the IS200TPROH1CBB Emergency Protection Terminal Board continues to deliver the performance, durability, and reliability that industrial users expect from GE. Whether used in a new installation or as a replacement for an existing board, the IS200TPROH1CBB Emergency Protection Terminal Board provides the signal interface functionality required for reliable and efficient emergency protection system operation.
