GE IC3600 Series Modules: IC3600VANB1D Annunciator Card —

Technical Dossier

Product Details And Specifications

GE IC3600 Series: Comprehensive Module Range and Technical Overview

The GE IC3600 series — commercially designated as the Speedtronic Mark I, Mark II, and Mark IV Gas Turbine Control System — represents one of the most widely deployed turbine control platforms in global heavy industry. Installed across petrochemical complexes, natural gas compression stations, nuclear auxiliary systems, and crude oil refineries, IC3600-based control panels have accumulated decades of field runtime in environments where continuous uptime is a non-negotiable operational requirement. The series was engineered by General Electric's Gas Turbine Division and remains active in facilities across North America, the Middle East, Southeast Asia, and Eastern Europe, many of which operate under long-term maintenance contracts that preclude full system replacement. The installed base of IC3600 hardware is estimated in the tens of thousands of panels globally, making reliable spare parts sourcing a persistent operational priority for plant engineers and reliability teams.

The Evolution of IC3600 Architecture

The IC3600 platform was introduced in the early 1970s as GE's first fully solid-state turbine control system, replacing relay-logic panels on Frame 3 through Frame 7 gas turbines. The original Mark I architecture used discrete analog and digital logic cards operating on a passive backplane with no serial communication bus — each card performed a dedicated function (sequencing, protection, temperature control, or annunciation) and interfaced directly with field wiring via terminal boards.

The Mark II revision introduced improved card-edge connectors, revised power supply regulation, and expanded I/O density. Mark IV, the final major iteration of the IC3600 physical form factor, added limited programmability and improved diagnostics while retaining backward mechanical compatibility with Mark I and Mark II card slots in most chassis configurations. This cross-generation compatibility is a critical factor for maintenance engineers: a Mark II chassis can often accept Mark IV replacement cards, but signal conditioning and jumper configuration must be verified against the original panel drawing set.

GE formally transitioned customers toward the Mark V (IC3600-series successor, introduced ~1991) and subsequently the Mark VI and Mark VIe platforms. However, the capital cost of full turbine control system replacement — typically USD 500,000 to USD 2,000,000 per unit including engineering and commissioning — means that a substantial portion of the global IC3600 installed base remains in service under extended lifecycle support arrangements. Cards in this series are no longer manufactured by GE; all procurement is through the secondary market, authorized repair facilities, or specialist distributors.

IC3600 Full Catalog & Functionalities (SKU List)

The following SKUs represent verified, commonly sourced modules within the GE IC3600 Speedtronic series. Each entry reflects a distinct functional role within the turbine control panel architecture.

Annunciator & Display Modules

• IC3600VANB1D: Annunciator card; drives alarm window displays for turbine fault and status annunciation panels.
• IC3600VANA1: Annunciator driver card, earlier revision; used in Mark I and early Mark II panels for alarm output conditioning.
• IC3600VANB1: Annunciator card, standard revision B; functionally equivalent to VANB1D with minor component-level differences.

Analog Input / Signal Conditioning Modules

• IC3600AFAA1A: Analog input card; processes thermocouple and RTD signals for exhaust temperature measurement.
• IC3600AFAA1B: Analog input card, revision B; improved cold-junction compensation for thermocouple inputs.
• IC3600AFBA1A: Analog signal conditioning card; used for speed and vibration transducer signal processing.
• IC3600AFCA1A: Analog output card; provides 4–20 mA outputs to fuel control actuators and IGV positioners.

Digital Input / Output Modules

• IC3600EPDA1A: Digital input card; 24 VDC discrete input module for limit switch and contact closure monitoring.
• IC3600EPDB1A: Digital output card; relay-driven discrete outputs for solenoid valve and contactor control.
• IC3600EPDC1A: Combined DI/DO card; mixed discrete I/O for sequencing logic applications.

Power Supply Modules

• IC3600PSCA1A: Primary DC power supply card; provides regulated +5 VDC and ±15 VDC rails to the IC3600 backplane.
• IC3600PSCB1A: Redundant power supply card; hot-standby configuration for critical turbine protection panels.
• IC3600PSCC1A: Battery-backed power supply module; maintains protection relay logic during AC supply interruption.

CPU / Sequencing / Logic Modules

• IC3600SCBA1A: Sequence control card; executes start/stop logic and permissive sequencing for gas turbine startup automation.
• IC3600SCBB1A: Sequence control card, revision B; expanded step capacity and improved diagnostic LED indication.
• IC3600TCRA1A: Temperature control card; implements exhaust temperature spread and over-temperature protection algorithms.
• IC3600SRBA1A: Speed reference card; generates speed setpoint signals for fuel control and governs turbine acceleration ramp rates.
• IC3600LRBA1A: Load reference card; manages load sharing and droop settings in parallel generator configurations.

Sourcing Hard-to-Find & Obsolete IC3600 Parts

The IC3600 series reached end-of-manufacture status with GE in the mid-1990s. As of 2026, no new production of IC3600 cards exists from the original equipment manufacturer. Procurement of these modules is exclusively through the secondary market, and supply quality varies significantly between sources.

Quality Control for the IC3600 Range

IC3600 modules present specific test challenges due to their passive backplane architecture and the absence of onboard self-diagnostics. DriveKNMS applies a structured verification protocol to all IC3600 cards prior to shipment. Each card undergoes visual inspection for capacitor ESR degradation, solder joint fatigue, and connector pin corrosion — failure modes characteristic of boards with 20–40 years of field service. Functional testing is performed using a dedicated IC3600 backplane test fixture that replicates the original panel power rail voltages (+5 VDC, ±15 VDC, +24 VDC) and exercises all active signal paths. Annunciator cards such as the IC3600VANB1D are tested against a simulated alarm matrix to verify all output driver channels. Analog cards are calibrated against NIST-traceable references. Digital I/O cards are cycled through full contact closure sequences. All tested units are issued a DriveKNMS inspection record documenting test date, technician ID, and pass/fail criteria for each functional parameter.

© 2026 DriveKNMS. All trademarks belong to their respective owners. Specifications are for reference only and subject to change without notice. Verify all parameters against official documentation before installation.