GE IC697CPX935-ED Series 90-70 Single-Slot CPU

Description

In large-scale industrial automation systems that have been running reliably for decades, the day the CPU finally throws a fatal watchdog fault is the day the entire plant stops cold. Engineers responsible for chemical reactors, turbine-generator sets, or pipeline compressor stations know that replacing a discontinued Series 90-70 controller is never as simple as swapping a card: you face months of revalidation, new safety-case paperwork, and budgets measured in millions. This is exactly the scenario the GE IC697CPX935-ED was created to prevent. As the last factory-refreshed, extended-support CPU935 variant — a single-slot 486DX4/100 MHz processor with 1 MB battery-backed SRAM and full Series 90-70 instruction set compatibility — the GE IC697CPX935-ED is the drop-in lifeline that keeps critical 90-70 installations alive well past the original end-of-life announcement. It delivers the same deterministic 0.4 ms/k Boolean scan times operators have trusted since the 1990s, but with refreshed components that eliminate the infant-mortality failures now plaguing twenty-five-year-old boards.

The GE IC697CPX935-ED occupies the CPU slot in any IC697CHSxxx VME rack and boots from the identical Logicmaster/VMIC/CIMPLICITY configuration files you already have archived. It supports the full 90-70 I/O capacity (up to 32 k words discrete, 8 k words analog, 256 k total registers) across local, Genius, and remote expansion racks. All three front-panel serial ports remain active (two RS-422/485, one RS-232) for programming, HMI, and third-party links, and the integrated 10Base-T Ethernet port provides direct CIMPLICITY or Proficy ME access without adding a separate CMM module. The on-board real-time clock is now Y2K+ compliant, and the firmware includes the final factory patch set that fixes the occasional floating-point exception that tripped earlier revisions under heavy PID load.

Specifying the GE IC697CPX935-ED is the fastest way to buy another ten to fifteen years for a 90-70 system that still meets all performance and safety requirements. The refreshed silicon and surface-mount redesign dramatically reduce heat-related drift and solder-joint failures that were starting to appear in the original 1998-era boards. Many sites swap the CPU during a planned outage, transfer the existing battery-backed memory contents with a simple EEPROM copy routine, and are back online in under an hour with zero logic changes. The result is continued operation of validated processes without the enormous cost and risk of a full DCS migration.

You’ll find the GE IC697CPX935-ED keeping nuclear-balance-of-plant systems running well past their original license extensions, controlling steam-turbine governor valves in 1970s-vintage power stations, and orchestrating pipeline SCADA master stations where even a weekend outage is politically impossible. It’s also the go-to replacement in large batch chemical plants where the original safety-instrumented functions were implemented entirely in ladder logic and revalidation would trigger a multi-year regulatory nightmare.

IC697CPX928-FD – 128 kB predecessor if you need exact memory match

IC697CPU781-JK – Expansion CPU for redundant configurations

IC697CMM711 – Legacy serial communications coprocessor often removed when using -ED Ethernet

IC697HSC700 – High-speed counter companion module

IC697PWR711 – 55 W power supply typically paired in same rack

IC697CHS782 – Hybrid VME/VMIC rack for CPU935-ED in newer installations

IC697BEM731 – Genius Bus Controller still supported under the -ED

Before inserting a GE IC697CPX935-ED, confirm the rack power supply is revision K or later and that backplane jumpers are set for single-CPU mode. Transfer the existing program and configuration using the EEPROM copy utility in Logicmaster 9.05 or later — it takes about four minutes. Leave the original battery in place for the transfer, then immediately replace it with a fresh IC697ACC701; the -ED will retain memory for over a year on the new lithium cell. After power-up, verify the top-line firmware banner shows “-ED” and run the built-in self-test routine from the front port. Most sites never touch the CPU again until the next planned decadal overhaul.