IS200DTBCG1A - Discrete Input/Output Terminal Board

TECHNICAL SPECIFICATIONS:

Part Number: IS200DTBCG1A
Manufacturer: General Electric
Series: Mark VI Speedtronic
Functional Designation: Discrete Input/Output Terminal Board (DTBC)
Discrete Input Capacity: 24 Channels (Galvanically Isolated)
Relay Output Capacity: 12 Channels (Form-C Architecture)
Excitation Nominal: 125 VDC or 24 VDC (Jumper Selectable)
Excitation Voltage Range: 18 to 132 VDC (Application Dependent)
Contact Wetting Current: 2.5 mA per channel (Nominal)
Interface Topology: 37-Pin D-Subminiature Connectors (JR1, JS1)
Input Filter Constant: 4 ms (Hardware Debounce)
Solenoid Driver Rating: 3.0 A per channel (Inrush Limit)
Surge Suppression: Metal-Oxide Varistors (MOV) integrated
Isolation Rating: 1500 V RMS (Group Isolation)
Operating Temperature: -30 to 65 Degrees Celsius
Dimensions: 23.8 cm high x 17.8 cm wide
Availability: In Stock

FUNCTIONAL DESCRIPTION:

The IS200DTBCG1A is a Discrete Input/Output Terminal Board within the Mark VI Speedtronic control framework. It acts as the primary electromechanical interface, managing the bidirectional flow of discrete telemetry between field-mounted transducers and the VME-based processing architecture. The module facilitates high-integrity signal acquisition for 24 dry contact inputs while driving 12 relay-based control outputs. The Contact Output Termination Module (DTBC) is located in Q11, Q21, and Q51. DTBC is connected to the 30 relays on the TCRA in location four of Q21 and Q51. Eighteen of the 30 outputs on DTBC in Q51 can be configured as solenoids using hardware jumpers on DTBC. The DTBC in Q11 is connected to the four contact output relays on the TCRA in location Q11. The hardware jumpers on the Q11 DTBC are specially configured for gas manifold blow-off valve control.

REDUNDANT TOPOLOGY AND BUS INTEGRATION

The Discrete Input/Output Terminal Board supports Simplex and Dual redundant configurations. Utilizing high-density JR1 and JS1 connectors, field signals fan out to redundant I/O processors (VCCC/VCRC). This parallel signal distribution ensures that the turbine control database maintains state-vector consistency even during a localized processor fault, upholding system fault-tolerant requirements.

PROGRAMMABLE EXCITATION PARAMETERS

The board features a reconfigurable excitation bus for synchronization with various field-side voltage requirements. Through onboard hardware jumpers, technicians designate a 24 VDC or 125 VDC excitation rail. This capability ensures optimal wetting current levels across field contacts, mitigating the effects of contact oxidation and maintaining low-impedance signal paths for critical protective interlocks.

INTEGRATED CONNECTOR ARCHITECTURE

The DTBC utilizes a specialized interface array for power distribution and signal relaying:

• JS1 through JS8: These connectors facilitate the acquisition of relay signals from the TCRA board in position four.
• J8: This port serves as the primary intake for solenoid excitation power from the TCPD board within the core.
• J15 & J16: These interconnected ports transmit 125 VDC power for contact outputs #16, #17, and #18. While utilized in the core, they are generally bypassed in core configurations.

HARDWARE CONFIGURATION & SOLENOID ACTUATION

Operational enablement of the DTBC follows a jumper-based protocol. The P1/M1 through P18/M18 headers function as solenoid enable mechanisms for contact outputs #1 through #18. For valid actuation, both jumpers in a pair must be populated to authorize solenoid power; removing both disables the circuit. An exception exists in the DTBC configuration when designated for gas manifold blow-off valve control.

GALVANIC ISOLATION AND TRANSIENT MITIGATION

The Discrete Input/Output Terminal Board incorporates galvanic isolation. Each discrete channel contains metal-oxide varistors (MOVs) and specialized capacitive filtering. This hardware-level protection attenuates common-mode noise and prevents high-voltage transients common in inductive load switching from entering the microprocessor environment.

WHY BUY FROM WOC:

World of Controls (WOC) is a specialized global authority in the lifecycle extension of GE Mark VI ecosystems, providing the IS200DTBCG1A in both UNUSED and REBUILT conditions to eliminate operational latency. Our quality-assurance protocol involves parametric testing, relay commutation cycle verification, dielectric integrity assessments, and automated point-to-point continuity mapping. By partnering with WOC, you secure hardware for peak deterministic performance, reinforced by 24/7 technical consultation and accelerated global logistics to keep your plant operational and efficient.

FREQUENTLY ASKED QUESTIONS:

What is the IS200DTBCG1A?

The IS200DTBCG1A is a hybrid Discrete Input/Output Terminal Board (DTBC) for the GE Mark VI Speedtronic system. It manages the simultaneous acquisition of 24 discrete contact inputs and the actuation of 12 relay outputs, acting as the centralized termination point for digital field telemetry.

How is the contact excitation voltage modulated on this board?

Excitation parameters are defined via onboard hardware jumpers, allowing the selection of a 24 VDC or 125 VDC rail to meet the wetting current requirements of field-side instrumentation.

What is the role of the J15 and J16 connectors?

These connectors carry 125 VDC power for specific contact outputs (#16�#18). Their use depends on the core configuration, being standard in but not typically used in architectures.

Does the DTBC board support Triple Modular Redundant (TMR) fanning?

No, the IS200DTBCG1A is for Simplex and Dual configurations. For TMR voting across three independent processors, specialized terminal boards such as the TBCI or DTBD are utilized.