GE Series 90-70 (IC697) Modules

Technical Dossier

Product Details And Specifications

GE Series 90-70 (IC697) Modules: Comprehensive Module Range and Technical Overview

The GE Series 90-70 — identified by the IC697 prefix — is one of the most widely deployed programmable logic controller (PLC) platforms in global heavy industry. Installed across petrochemical refineries, nuclear power generation facilities, offshore platforms, pulp and paper mills, and large-scale chemical processing plants, the Series 90-70 established GE Fanuc Automation's position as a tier-one DCS/PLC supplier throughout the 1990s and 2000s. Its 9-slot and 17-slot VME-based backplane architecture, combined with a deterministic scan cycle and robust I/O density, made it the preferred choice for safety-critical continuous process environments where mean time between failures (MTBF) and long-term parts availability are non-negotiable procurement criteria.

The IC697ALG230 is a 16-channel analog input module operating within this rack system, accepting 4–20 mA or 0–20 mA current signals, with 12-bit resolution and configurable channel scanning. It is a direct replacement candidate for legacy analog instrumentation loops in refineries and chemical plants still operating Series 90-70 infrastructure.

The Evolution of IC697 (Series 90-70) Architecture

The Series 90-70 platform was introduced by GE Fanuc Automation in the late 1980s as a high-end modular PLC targeting large process industries. Its VMEbus-derived backplane provided a 32-bit data path — a significant advancement over the 8- and 16-bit architectures of competing platforms at the time.

Generation 1 (1988–1995): Initial CPU modules (IC697CPU731, IC697CPU771) established the rack-and-slot architecture. I/O modules used parallel backplane communication with fixed address mapping. Programming was performed via Logicmaster 90-70 software on DOS-based workstations.

Generation 2 (1995–2003): Introduction of enhanced CPUs (IC697CPU781, IC697CPU788) with expanded memory and Ethernet options. The IC697CMM741 and IC697CMM742 communication modules added Genius Bus and serial connectivity. Proficy Machine Edition replaced Logicmaster as the primary programming environment.

Generation 3 / Transition Era (2003–2012): GE began positioning the PACSystems RX7i (IC698 series) as the architectural successor, maintaining physical and backplane compatibility with Series 90-70 racks. IC698 CPUs can operate in IC697 racks, providing a migration path without full hardware replacement — a critical factor for plants with 20+ year operational horizons.

Current Status (2012–Present): The IC697 series is in the mature/end-of-life phase. GE (now Emerson Automation Solutions following the 2023 acquisition of GE's automation portfolio) no longer manufactures new IC697 modules. All procurement is sourced through authorized repair depots, surplus distributors, and specialist spare parts suppliers such as DriveKNMS. Long-term maintenance support — including board-level repair, functional testing, and exchange programs — is the primary service model for this platform.

IC697 Full Catalog & Functionalities (SKU List)

The following represents a cross-functional index of the most commonly sourced IC697 modules, organized by functional category. All models listed are verified members of the GE Series 90-70 platform.

CPU & Controller Modules

IC697CPU731: Series 90-70 CPU, 512KB user memory, 0.4ms/K logic scan rate.
IC697CPU771: Enhanced CPU, 1MB memory, floating-point math co-processor support.
IC697CPU781: High-performance CPU, 2MB memory, Ethernet TCP/IP option module compatible.
IC697CPU788: Advanced CPU with 6MB memory, supports up to 512 I/O points per rack.
IC697CPU789: Top-tier Series 90-70 CPU, 6MB memory, redundancy-capable configuration.

Analog Input Modules (AI)

IC697ALG230: 16-channel analog input, 4–20 mA / 0–20 mA, 12-bit resolution, configurable scan.
IC697ALG231: 16-channel analog input, ±10V / 0–10V voltage input, 12-bit resolution.
IC697ALG320: 8-channel analog input, high-speed, 14-bit resolution, ±10V range.
IC697ALG321: 8-channel analog input, thermocouple/RTD compatible, cold junction compensation.

Analog Output Modules (AO)

IC697ALG390: 8-channel analog output, 4–20 mA current, 12-bit resolution, isolated outputs.
IC697ALG391: 8-channel analog output, ±10V voltage, 12-bit, short-circuit protected.

Digital Input Modules (DI)

IC697MDL340: 32-channel 24VDC digital input, source/sink configurable, LED status per channel.
IC697MDL341: 16-channel 120VAC digital input, optical isolation, 15ms input filter.
IC697MDL653: 32-channel 24VDC digital input, high-density, group isolated.

Digital Output Modules (DO)

IC697MDL740: 32-channel 24VDC digital output, 0.5A per channel, short-circuit protection.
IC697MDL741: 16-channel relay output, Form C contacts, 2A per channel, 120/240VAC rated.
IC697MDL753: 32-channel 24VDC output, high-density, group fused protection.

Communication & Network Modules

IC697CMM741: Genius Bus Controller, supports up to 32 Genius devices per bus circuit.
IC697CMM742: Dual Genius Bus Controller, redundant bus architecture support.
IC697BEM711: Ethernet Interface Module, 10BaseT, Modbus TCP and SRTP protocol support.
IC697PCM711: Programmable Co-processor Module, executes C-language application programs.

Power Supply Modules (PS)

IC697PWR710: 120/240VAC input power supply, 30W output, standard rack supply.
IC697PWR711: 120/240VAC input, 60W high-capacity power supply for fully loaded racks.
IC697PWR748: 24VDC input power supply, 30W, for DC-powered panel installations.

Sourcing Hard-to-Find & Obsolete IC697 Parts

With GE's IC697 series formally discontinued from active production, the global installed base — estimated in the tens of thousands of rack systems across refineries, power stations, and water treatment facilities — depends entirely on the secondary market for hardware continuity. DriveKNMS maintains a dedicated inventory program for Series 90-70 components, with particular focus on high-attrition modules including analog I/O cards, CPU boards, and communication modules.

Our sourcing protocol for IC697 parts includes: direct acquisition from decommissioned plant assets, exchange programs with facilities undergoing PACSystems migration, and partnerships with authorized GE service centers for tested surplus stock. All IC697 modules sourced by DriveKNMS are subject to full functional verification before dispatch. For end-users operating plants with 5–15 year remaining operational life, we recommend establishing a consignment stock agreement to guarantee availability of critical spare modules — particularly CPU, power supply, and primary analog I/O cards — without capital commitment to full inventory ownership.

Quality Control for the IC697 Range

The Series 90-70 backplane uses a parallel VME-derived bus architecture that requires specific test procedures distinct from standard PLC module verification. DriveKNMS applies the following QC protocol to all IC697 modules prior to shipment:

Backplane Communication Test: Each module is seated in a live IC697 rack and verified for correct slot addressing and backplane data transfer. Modules that fail to enumerate correctly are rejected regardless of visual condition.

Analog Channel Calibration (AI/AO modules): All analog input and output modules — including the IC697ALG230 — undergo per-channel calibration verification using traceable reference instruments. Current loop accuracy is verified at 4 mA, 12 mA, and 20 mA setpoints. Offset and gain errors exceeding ±0.1% of full scale are flagged for recalibration or rejection.

CPU Memory and Scan Integrity: CPU modules are loaded with a standardized diagnostic ladder program and run for a minimum 4-hour burn-in cycle. Memory integrity, scan time consistency, and communication port functionality (serial, Ethernet where applicable) are logged and included with shipment documentation.

Power Supply Load Testing: IC697 power supply modules are tested at 100% rated load for 2 hours. Output voltage ripple, regulation under step load, and thermal performance are measured against GE's original published specifications.

Visual and Component Inspection: All boards undergo inspection for capacitor condition (electrolytic aging is the primary failure mode in 20+ year old modules), solder joint integrity, and connector pin condition. Boards with degraded electrolytic capacitors are recapped prior to functional test.