The DS200DTBCG1A (Contact Output Termination Module) is a critical component within General Electric's (GE) SPEEDTRONIC Mark V LM Turbine Control System, categorized as a Printed Wiring Terminal Board (TB). This module is primarily used within the Digital Input/Output (I/O) cores, serving as the termination and distribution hub for contact output signals. The DS200DTBCG1A module plays a pivotal bridging role in the turbine control system, converting internal controller logic commands into physical actions. By driving relays or solenoids, it controls various switch-type actuators for the gas turbine and its auxiliaries, such as valves, pumps, fans, and ignition systems.
Within the architecture of the Mark V LM control system, the Digital I/O cores (e.g., <Q11>, <Q21>, <Q51>) handle a large volume of discrete signals. The DS200DTBCG1A module is installed within these cores, working in close conjunction with the Digital I/O Board (TCDA) and the Relay Output Boards (TCRA) to complete the final wiring, power distribution, and output type configuration for the output channels. Its design embodies industrial-grade standards of high reliability, flexible configuration, and ease of maintenance, forming a crucial hardware foundation for ensuring the safe, stable, and efficient operation of gas turbines.
2. Product Model & Positioning
Model: DS200DTBCG1A
Full Name: Contact Output Termination Module
Parent System: SPEEDTRONIC Mark V LM Turbine Control System
Primary Function: Terminal connection for contact output signals, power distribution, and hardware configuration of output type (dry contact / powered [solenoid] contact).
Installation Location: Within the Digital I/O cores <Q11>, <Q21>, <Q51> of the Mark V LM controller.
3. Role & Signal Flow within the Control System
The DS200DTBCG1A module resides at the final actuation stage of the Mark V LM control signal flow:
Control Command Generation: The Control Sequence Program (CSP) in the Control Engine <R> generates logic control signals based on turbine status and operator commands.
Signal Transmission: Logic signals are sent to the appropriate I/O Engines (e.g., <R1>, <R5>) via the COREBUS network.
I/O Processing: The I/O Engine relays the signals to the TCDA board in the Digital core <Qxx> via the IONET network.
Relay Driving: The TCDA board converts the logic signals into drive commands, sent via the JO connector to the TCRA board, energizing or de-energizing specific relays.
Terminal Execution: The state change of the relay contacts on the TCRA board is transmitted to the DS200DTBC module via the JS1-JS8 connectors.
Power Output & Field Connection:
If the channel is configured as a "dry contact" on the DTBC, the relay contacts connect directly to the module's terminal blocks. User-supplied control power connects to the field device coil via these terminals.
If configured as a "solenoid output," the DTBC module routes the internal 125 V DC power (from J8, etc.) through the closed relay contacts directly to the corresponding terminal block, powering the connected solenoid.
Field Device Actuation: Finally, electrical energy drives the field actuator (e.g., fuel valve, bypass valve, pump) to complete the control objective.
4. Installation, Configuration & Wiring Guidelines
4.1 Installation Notes
The DS200DTBCG1A, as a terminal board, is installed in a designated slot within the Digital I/O core (typically on the front or side of the core).
Ensure all controller power is OFF before installation and observe anti-static precautions.
During installation, ensure connectors (JS series, J8, etc.) are firmly mated with corresponding boards (TCRA, power cables), paying attention to cable orientation (usually aligned by color stripe or Pin1 marker).
4.2 Hardware Jumper Configuration
This is a critical step in using the DS200DTBCG1A, directly determining the nature of the output channel.
Jumper Identification: For standard solenoid output configuration, jumpers appear in pairs, labeled Px and Mx (where x=1 to 18, corresponding to output channels 1 to 18).
Configuration Method:
Special Configuration (e.g., <Q11> Gas Valve Control): Must strictly follow the drawings and signal flow diagrams in Appendix D. Do not apply standard jumper rules.
Configuration Principle: Always ensure each output channel has only one power source (either internal via jumpers OR external) to avoid power conflicts and potential equipment damage.
4.3 Field Wiring
Connect cables from field actuators (relay/contactor coils, solenoids, etc.) to the correct screw terminals on the DTBC module according to engineering drawings.
Distinguish between Normally Open (NO), Normally Closed (NC), and Common (COM) terminals.
For dry contacts, also connect the user-supplied control power wires.
Wiring should be secure and comply with local electrical codes and the National Electrical Code (NEC).
5. Typical Application Scenarios
The DS200DTBCG1A module is widely used in various industrial fields requiring reliable discrete control, especially in gas turbine control. Typical applications include:
Fuel System Control: Driving solenoids for gas fuel shut-off valves, stop ratio valves, purge valves, etc.
Lube & Hydraulic Oil Systems: Controlling contactors for lube oil pumps, hydraulic oil pumps.
Cooling & Ventilation Systems: Operating cooling fans, louver actuators.
Ignition System: Providing power control for high-energy ignition transformers (typically using dedicated AC output channels).
Auxiliary Equipment Sequencing: Controlling the start/stop sequence of auxiliary equipment per start-up/shutdown logic, such as air compressors, wash pumps.
Protection & Interlocking: Executing trip commands from the protection system to rapidly close critical valves.
In applications like the LM6000 aeroderivative gas turbine, the DS200DTBC module (particularly the specially configured version in the <Q11> core) is essential for implementing complex safety functions such as gas manifold purging and load coupling shear protection.
6. Maintenance, Diagnostics & Troubleshooting
6.1 Routine Maintenance
Periodically check terminal screws for tightness.
Keep the module and surrounding area clean and free of dust accumulation.
Before performing any maintenance, always follow safety procedures: de-energize power and verify the absence of hazardous voltage.
6.2 Diagnostic Features
The control system's diagnostics can monitor the drive status of the TCRA board relay coils.
The logical status of output points can be viewed via diagnostic screens (DIAGC) on the operator interface (HMI).
For channels configured as solenoid outputs, the system may perform limited diagnostics, such as current monitoring.
6.3 Common Faults & Troubleshooting
Output Point Not Actuating:
Check if the CSP logic has issued the command.
Confirm the logical status of the output point is "TRUE" on the HMI.
Check if the indicator light (if present) for the corresponding relay on the TCRA board is illuminated.
Use a multimeter to measure at the DTBC terminals: for dry contacts, check relay contact continuity; for powered contacts, check for voltage output.
Verify hardware jumper configuration is correct (a common error source).
Solenoid Output Power Abnormal:
Module Communication or Hardware Failure: If multiple channels fail simultaneously, consider faults with the TCRA board, TCDA board, or IONET communication. Refer to Chapter 8 of the manual for systematic troubleshooting.
