The DS200TBQBG1A Input Termination Module is a versatile front-end interface board within the General Electric (GE) Industrial Systems SPEEDTRONIC Mark V LM Gas Turbine Control System, dedicated to handling various analog and pulse signals. Acting as the critical bridge connecting sensitive field sensors to the core control boards (TCQA, TCQC), the DS200TBQBG1A module plays the role of "signal gatekeeper" and "format converter" at the source of the signal acquisition chain. It is located in Slot 7 of the <R2> and <R3> analog I/O cores, serving as the hardware foundation for the system to acquire vibration, process pressure, speed, and general voltage/current signals, and perform initial conditioning and routing.
The DS200TBQBG1A module's design philosophy centers on providing high on-site adaptability and configuration flexibility. Through precision terminal blocks and configurable hardware jumpers, the TBQB can accept raw signals from various industrial sensors such as seismic velocity sensors, proximity probe transmitters, and pressure transmitters, converting them into standardized signals processable by the internal control system boards. Its stability and reliability directly impact the accuracy of critical control functions such as vibration protection, performance monitoring, and surge prevention, making it a vital front-end component for ensuring the safe, stable, and efficient operation of gas turbines.
2. Product Functions and Features
2.1. Core Functions
As a purely passive termination interface board containing no active processor, the DS200TBQBG1A module's primary functions are signal aggregation, distribution, isolation, and preliminary configuration:
Multi-Channel Signal Aggregation: Provides a centralized terminal block for connecting up to 12 channels of seismic (velocity) vibration sensor inputs, 2 channels of general-purpose analog inputs (configurable as 4-20 mA current or ±10 V DC voltage), 2 channels of analog inputs with excitation power, 1 channel of critical pressure transmitter input (typically for compressor stall detection), and multiple pulse rate inputs.
Signal Routing and Distribution: Internally routes different signals accurately to corresponding downstream board connectors via printed circuits.
Vibration and General Analog Signals: All vibration signals and configurable analog signals are sent via the JGR connector to the TCQA Analog I/O board in the respective core for processing.
Pulse and Dedicated Pressure Signals: Pulse rate inputs and compressor stall detection pressure signals are sent via the JHR connector to the TCQC Analog I/O Expander board in the respective core for processing.
Signal Type Hardware Configuration: This is the core value of the TBQB. Through a series of hardware jumpers, field engineers can flexibly define input signal types without changing field wiring.
Current/Voltage Mode Selection: Can configure analog input channels to receive either 4-20 mA current signals or ±10 V DC voltage signals, adapting to transmitters with different output types.
Excitation Power Provision: For transmitters requiring external power (e.g., 2-wire pressure transmitters), the TBQB can be configured via jumpers to provide 21 V DC isolated power from the internal supply.
Input Impedance (Burden Resistor) Matching: Installs burden resistors of appropriate values for current input channels via jumpers, converting current signals into measurable voltage signals.
Architectural Flexibility: A unique application feature is that, in standard configurations, the TBQB terminal board in the <R2> core actually serves the TCQA and TCQC boards in the <R1> core. This design allows specific high-importance signals (like vibration signals from the <R2> TBQB) to be centrally routed to the main control core <R1> for processing, reflecting an optimized system layout.
2.2. Design Features
High-Density, Clear Terminal Layout: Utilizes industrial-grade terminal blocks with clear channel markings, supporting direct connection of field cables, simplifying installation and commissioning.
Passive, High-Reliability Design: As a pure wiring and jumper configuration board with no active components, it has an inherently low theoretical failure rate and offers high long-term operational stability.
Excellent Noise Immunity: Optimized board-level routing, isolated power paths, and shielding connection options effectively suppress electromagnetic interference (EMI) from industrial environments, ensuring the integrity of weak vibration and pulse signal transmission.
Maintenance and Diagnostic Friendliness: The status of each input channel can be monitored via the downstream TCQA/TCQC boards. Jumper settings are clearly visible, facilitating field inspection and troubleshooting.
Backward Compatibility Considerations: Retains jumper positions for legacy applications (e.g., compressor stall detection pressure signal fan-out), protecting customer assets and upgrade paths.
3. Application Fields
As a key device at the signal acquisition layer, the DS200TBQBG1A module's applications are entirely focused on turbine monitoring and protection needs:
Vibration Monitoring and Protection System: This is the DS200TBQBG1A's primary function. It connects seismic velocity sensors installed at key locations like bearing housings to continuously monitor vibration amplitude of critical components such as high, intermediate, and low-pressure rotors and generators. These signals are the core basis for assessing mechanical health and triggering vibration high-alarm and high-high trip protection, crucial for preventing catastrophic mechanical failures.
Compressor Anti-Surge Control: By connecting pressure transmitters (typically 4-20 mA) at the compressor outlet or inlet, it provides real-time pressure data to the control system. This data, combined with flow and speed signals, is used to execute complex anti-surge control algorithms, ensuring the compressor always operates within its stable operating region and preventing surge-induced damage.
Process Parameter Monitoring: The general-purpose 4-20 mA / ±10V input channels can be used to connect transmitters for various auxiliary systems, such as lube oil pressure/temperature, fuel gas pressure/temperature, cooling water pressure, air mass flow, etc., providing data for performance calculations, efficiency optimization, and auxiliary system control.
Auxiliary Speed Signal Input: The pulse input channels provided to the TCQC board can serve as a supplement to the primary speed monitoring system (from the <P1> core) or for monitoring speeds like accessory drive speeds.
4. Product Advantages
Unparalleled Configuration Flexibility: The BJ8-BJ15 jumper set is the soul of the DS200TBQBG1A. It allows field engineers, at the final moment before commissioning, to simply match the board to the actual transmitter type (current or voltage) via jumper operation based on what arrives on-site. This eliminates the need for wiring changes or waiting for specific board models, significantly shortening commissioning cycles and reducing spare parts inventory complexity.
Maximized Signal Integrity: As a dedicated terminal board, its design focuses on signal purity. Optimized trace routing, power isolation, and shielding design ensure weak vibration analog signals and sensitive pulse signals are protected from power supply noise and crosstalk before entering the complex digital processing system.
Optimized System Architecture: The design where the <R2> core TBQB serves the <R1> core embodies a functional partitioning philosophy. It centrally routes all critical vibration and performance monitoring signals to the main control core <R1>, simplifying the data sources for control logic, while allowing the <R2> and <R3> cores to handle other expansion or redundant functions, creating a clear and efficient system architecture.
High Reliability and Maintainability: Passive design leads to inherent high reliability. Clear labeling, intuitive jumper layout, and standard connectors make daily inspection, fault diagnosis, and module replacement quick and straightforward, minimizing downtime.
Powerful On-Site Adaptability: Whether for traditional 4-20 mA instruments, specific sensors with ±10V output, or 2-wire instruments requiring remote power, the TBQB can easily adapt through jumper configuration, meeting equipment interfacing requirements across different regions and project standards globally.
Clear Division of Responsibility: The TBQB clearly delineates the boundary between signal interfacing and signal processing. Field maintenance personnel need only focus on the correctness of wiring and jumpers on the TBQB, while control engineers concentrate on software configuration in the downstream TCQA/TCQC. This separation enhances collaboration efficiency and system manageability.
5. Installation, Configuration, and Maintenance Guide
5.1. Installation
The DS200TBQBG1A module is installed in the designated location (Slot 7) of the <R2> or <R3> core frame.
Ensure controller power is disconnected before installation.
Securely fasten cables from field sensors to the corresponding terminal points according to the clear labels on the terminal block. Pay attention to signal polarity (e.g., "+" and "-" for current inputs).
Using the provided flat cables, reliably insert the JGR connector into the corresponding socket on the TCQA board of the relevant core (the <R1> core for the <R2> TBQB, and the <R3> core for the <R3> TBQB). Insert the JHR connector into the corresponding socket on the TCQC board of the relevant core. Pay attention to cable orientation (align the "trace" edge with pin 1).
5.2. Hardware Configuration (Critical Step)
Correct jumper configuration is a prerequisite for DS200TBQBG1A operation and must be completed and reviewed against design drawings before power-up.
Current/Voltage Mode Selection (BJ8-BJ15): This is the most common configuration. Based on the transmitter output type connected to each channel:
If the transmitter outputs a 4-20 mA current, install the corresponding jumper, typically to connect the onboard precision burden resistor (e.g., 250 ohms), converting current to voltage.
If the transmitter outputs ±10 V DC voltage, remove or change the jumper position to allow the signal to enter the high-impedance voltage measurement circuit directly.
Always refer to the signal flow diagrams (e.g., Appendix D) and project-specific wiring diagrams. Each channel's configuration is independent.
Excitation Power Enable: For 2-wire transmitters requiring 21V DC excitation from the TBQB, the excitation power loop must be connected via jumpers (typically specific combinations within BJ8-BJ15).
Compressor Stall Signal Configuration (BJ1-BJ7): In legacy or specific applications requiring this function, set BJ1-BJ4 (signal fan-out) and BJ5-BJ7 (burden resistor installation) as per design requirements.
After configuration, perform spot checks using a multimeter in continuity mode to verify jumper connections match expectations, and compare against the settings on the HMI's "Hardware Jumper Screen."
5.3. Software-Related Configuration
The DS200TBQBG1A itself has no software configuration. However, the physical state of its jumpers must exactly match the software I/O configuration settings within the downstream TCQA and TCQC boards.
In the I/O Configuration Editor on the HMI, engineers must define "signal type" (e.g., "4-20 mA", "±10V"), engineering units, range, filtering constants, and alarm thresholds for each channel connected via the TBQB that match the hardware jumper settings.
For example, if Channel 1 is set to "4-20 mA Input" via jumpers on the TBQB, the I/O configuration for that channel must also select the "4-20 mA" type and correctly set its corresponding CSDB full-scale value. Any mismatch will cause reading errors.
5.4. Maintenance and Troubleshooting
6. Safety Precautions
De-energized Operation: Although work on the DS200TBQBG1A typically involves low-voltage signal wiring, the connected TCQA/TCQC boards may have operating voltages. For safety, before performing any wiring, jumper changes, or disassembly on the TBQB, follow safety procedures by disconnecting power to the relevant core (via the corresponding switch in the <PD> core) and implementing Lockout/Tagout (LOTO).
Correct Configuration is the Foundation of Safety: Incorrect jumper configuration (e.g., connecting a voltage signal to a channel configured for current) may overload the downstream input circuit or even damage expensive precision front-end components on the TCQA/TCQC boards. Configuration work must be performed and verified by trained personnel using current drawings.
Beware of Field Signal Hazards: Although the TBQB handles low-level signals, extension cables for certain field sensors (e.g., some types of proximity probes) may run near high-voltage equipment, posing a risk of induced high voltage. Remain vigilant during operations.
Electrostatic Discharge (ESD) Precautions: Although the TBQB is a passive board, basic ESD prevention measures are still recommended during replacement or handling to avoid human static electricity affecting other sensitive boards nearby.
