GE IS200TRLYH2C Relay Output with Contact Sensing Terminal Board

Technical Dossier

Product Details And Specifications

GE IS200T Series Technical Notes

The GE IS200T series constitutes the primary I/O terminal board family for GE's Mark VI and Mark VIe Turbine Control Systems — the dominant distributed control platform deployed across heavy industrial sectors including petrochemical refineries, nuclear power stations, combined-cycle gas turbine plants, and offshore oil & gas facilities. The IS200TRLYH2C specifically functions as a relay output board with integrated contact sensing, providing hardwired discrete output capability with feedback verification — a critical requirement in safety-instrumented and high-availability turbine control architectures. Installed base for the Mark VI/VIe platform spans tens of thousands of units globally, making IS200T series terminal boards among the most actively sourced industrial spare parts in the power generation and process industries.

The Evolution of IS200T Series Architecture

The IS200T terminal board family was introduced alongside the GE Mark VI control system in the mid-1990s as a modular replacement for the earlier Mark V hardwired I/O architecture. The Mark VI platform standardized on a VME-based backplane with dedicated terminal boards handling signal conditioning, isolation, and field wiring termination — separating the I/O interface layer from the controller logic layer. This architecture allowed field replacement of terminal boards without disturbing controller modules.

IS200T Series Full Catalog & Functionalities (SKU List)

Relay Output & Contact Sensing Boards

• IS200TRLYH1A: Relay output terminal board, H1 revision, standard contact configuration
• IS200TRLYH1B: Relay output terminal board, H1B revision, updated relay coil specs
• IS200TRLYH2A: Relay output board with contact sensing, H2A revision, enhanced isolation
• IS200TRLYH2B: Relay output board with contact sensing, H2B revision, conformal coated
• IS200TRLYH2C: Relay output with contact sensing terminal board, H2C revision — primary active spare
• IS200TRLYH2D: Relay output with contact sensing, H2D revision, latest hardware iteration

Analog Input / Output Boards

• IS200TAIAH1A: Analog input terminal board, 16-channel, 4–20 mA / 0–10 V configurable
• IS200TAIAH1B: Analog input terminal board, H1B revision, improved EMI filtering
• IS200TAOAH1A: Analog output terminal board, 8-channel, 4–20 mA output for actuator control

Digital Input / Output Boards

• IS200TDIAH1A: Discrete input terminal board, 24 VDC, 32-channel field wiring interface
• IS200TDOAH1A: Discrete output terminal board, solid-state, 32-channel, 24 VDC sourcing
• IS200TBCIH1C: Bus controller interface terminal board, Mark VI VME backplane interface

Thermocouple / RTD Input Boards

• IS200TTURH1C: Turbine thermocouple input terminal board, 12-channel, J/K/T type
• IS200TTURH2C: Thermocouple input board, H2C revision, extended temperature range support
• IS200TREGH1A: Speed/acceleration input terminal board for turbine speed sensing circuits

Communication & Power Interface Boards

• IS200TSVOH1A: Servo output terminal board, electrohydraulic valve interface, ±10 V / 4–20 mA
• IS200TPROS1A: Protection relay output terminal board, trip-rated, SIL-compatible wiring interface

Quality Control for the IS200T Series Range

IS200T terminal boards present specific test challenges due to their mixed-signal architecture: relay output circuits, contact sensing feedback loops, and field wiring termination blocks must all be verified independently and in combination. DriveKNMS applies a structured test protocol for the IS200TRLYH2C and related relay output boards: relay coil continuity and pull-in/drop-out voltage verification; contact resistance measurement across NO/NC contacts under rated load; contact sensing circuit loop integrity test simulating field wiring conditions; isolation resistance test between relay coil, contact circuits, and chassis ground (minimum 100 MΩ at 500 VDC); and visual inspection of terminal block condition, PCB trace integrity, and conformal coating coverage. Boards that pass all stages are issued a DriveKNMS test certificate with revision, serial number, and test date recorded. Units with marginal relay contact wear are downgraded to exchange-core status and not listed as ready-to-install spares.