GE IS200 Series Modules IS200EDEXG1AFA Exciter De-Excitation Board

Technical Dossier

Product Details And Specifications

GE IS200 Series Technical Notes

The Evolution of IS200 Architecture

The IS200 series was introduced as the hardware backbone of GE's Mark VI Turbine Control System in the mid-1990s, succeeding the Mark V platform (TCCA, TCPS, TCQC boards). The Mark VI architecture standardized VME-based backplane communication with dedicated IONet Ethernet for I/O data transport, replacing the earlier serial ARCNET topology of Mark V. Key architectural milestones include:

• Mark VI (1995–2005): Initial IS200 deployment. Single and triple-redundant (TMR) configurations. IONet at 10 Mbps. Boards communicate via a passive backplane with dedicated slot assignments.
• Mark VIe (2005–present): Ethernet-based distributed I/O. IS200 boards retained physical form factor but gained EtherNet/IP and Profibus DP compatibility. IONet upgraded to 100 Mbps. Introduced the UCSC and UCVEH controller modules.
• Mark VIeS (Safety, 2012–present): SIL 2/3 certified variant. IS200 I/O modules qualified under IEC 61508. Adds dedicated safety I/O boards (STCI, SVOA) alongside standard IS200 catalog.

Compatibility note: IS200 boards designed for Mark VI are generally not hot-swappable into Mark VIe racks without firmware and configuration validation. Backplane connector pinouts are physically identical, but firmware versioning and IONet protocol handshake differ between generations.

IS200 Full Catalog & Functionalities (SKU List)

Controllers & Processors

• IS200UCVEH2A: Mark VIe primary controller, dual Ethernet IONet ports, 256 MB RAM
• IS200UCSCH1A: Mark VIe safety controller, SIL 2 rated, redundant watchdog
• IS200EPDLH1A: Ethernet-based process data link module, 100 Mbps IONet interface

Analog Input (AI) Modules

• IS200AEPAH1A: 16-channel analog input, 4–20 mA / 0–10 V, 12-bit resolution
• IS200AEAAH1A: Analog input module, thermocouple and RTD compatible, cold-junction compensation
• IS200ATBAH1A: Analog terminal board, field wiring interface for AEAA/AEPA modules

Digital Input (DI) Modules

• IS200EDISH1A: 24-channel digital input, 24 VDC, optically isolated, DIN rail mount
• IS200VTURH2A: Turbine speed/vibration input module, dual-channel magnetic pickup interface

Digital Output (DO) Modules

• IS200EDOEH1A: 16-channel digital output, relay contact, 2A per channel, 24–125 VDC
• IS200TRLYH1A: Relay output terminal board, field interface for EDOE modules

Excitation & Power Modules

• IS200EDEXG1AFA: Exciter de-excitation board; manages controlled field discharge during generator trip events; interfaces with static excitation systems; compatible with Mark VI TMR and simplex configurations
• IS200EPSMH1A: Power supply module, 28 VDC output, redundant input 85–264 VAC
• IS200EPDLH1A: Power distribution and logic module, backplane power sequencing

Communication & Network Modules

• IS200ECTBH1A: Ethernet communication terminal board, RJ45 IONet interface
• IS200EPCTG1A: Profibus DP gateway module, master/slave configurable, up to 12 Mbps
• IS200EACFH1A: AC feedback module, generator voltage and current sensing, 3-phase input

Servo & Valve Control

• IS200VSSVH2A: Servo valve driver module, ±100 mA output, LVDT position feedback
• IS200VSVOH1A: Servo output terminal board, field wiring for VSSV modules

Sourcing Hard-to-Find & Obsolete IS200 Parts

GE formally transitioned Mark VI support to legacy status in 2018, with Mark VIe remaining in active support through the current decade. As a result, a significant portion of the IS200 catalog — particularly first-generation Mark VI boards manufactured between 1995 and 2005 — is no longer available through OEM channels. DriveKNMS maintains a dedicated inventory of tested IS200 surplus and refurbished modules to support lifecycle extension programs for operators who cannot justify a full DCS migration.

Specific sourcing capabilities include: end-of-life boards such as IS200EDEXG1AFA, IS200AEPAH1A, and IS200EDISH1A; cross-reference matching for superseded part numbers; and emergency urgent RFQ handling for critical plant outage scenarios. All sourced units are accompanied by full traceability documentation and test records.

Quality Control for the IS200 Range

IS200 modules present specific test challenges due to their backplane-dependent communication architecture and mixed analog/digital signal paths. DriveKNMS applies the following test protocol to all IS200 units prior to dispatch:

• Backplane continuity test: All edge connector pins verified against GE IS200 backplane pinout specification using automated bed-of-nails fixture.
• IONet communication validation: Module inserted into live Mark VI/VIe test rack; IONet packet exchange confirmed at rated speed (10/100 Mbps depending on generation).
• Analog channel calibration: For AI/AO modules, each channel verified against NIST-traceable reference source; linearity error must be within ±0.1% of full scale.
• Excitation board functional test (IS200EDEXG1AFA specific): De-excitation discharge circuit activated under controlled resistive load; field suppression timing verified against GE specification GEH-6721.
• Thermal soak: 4-hour burn-in at 55°C ambient to screen latent component failures.
• Final inspection: Visual inspection for PCB delamination, capacitor bulge, and connector corrosion; conformal coating integrity check under UV lamp.