GE IC697CPM925-BB 64 MHz 32-Bit Floating Point CPU

Description

The GE IC697CPM925-BB solves the challenge of delivering high-performance, floating-point processing in demanding industrial automation applications where complex calculations are essential for precise control. In many legacy Series 90-70 systems—still prevalent in facilities that prioritize proven reliability over full modernization—standard CPUs struggle with math-intensive tasks like advanced PID loops, flow computations, temperature profiling, or motion coordination, leading to slower scan times, reduced accuracy, or the need for external coprocessors that add complexity and potential failure points. The GE IC697CPM925-BB is a high-speed, single-slot CPU built around a 64 MHz 80486DX2 processor with native floating-point support, enabling efficient handling of real-time floating-point operations without performance penalties.

This makes it particularly valuable in process-oriented environments where algorithms require decimal precision, such as continuous flow regulation, chemical dosing, or energy management systems. Engineers often turn to it during upgrades of existing racks to boost throughput and computational capability while retaining compatibility with established I/O, Genius networks, and programming tools. By providing robust execution speeds (0.4 µs per Boolean function) and support for large I/O counts (up to 12K discrete/8K analog), GE IC697CPM925-BB helps maintain high reliability in process control, ensuring deterministic response even as application logic grows more sophisticated or data volumes increase.

The GE IC697CPM925-BB serves as the central processing unit in GE Series 90-70 PLC racks, occupying a single slot and interfacing directly with the VME-style backplane to coordinate all rack-resident modules, including discrete/analog I/O, smart option cards, and communications coprocessors. It executes user programs configured via MS-DOS or Windows-based programming software (like Logicmaster 90 or VersaPro), supporting ladder logic, structured text, and function blocks with floating-point math capabilities for precise calculations in control algorithms.

In the automation hierarchy, it sits at the core of the control layer, communicating with field devices through Genius I/O, Field Control stations, or optional LAN/Ethernet modules for integration with HMIs, SCADA, or peer PLCs. Front-panel features include a three-position RUN/STOP switch, memory protect keyswitch, serial ports for programming/diagnostics, and status LEDs for quick health checks. The CPU handles program storage in battery-backed RAM (typically 1 MB in this revision), with password protection and keyswitch security to safeguard configurations. This design allows seamless operation in standalone or networked setups, offloading complex math from slower processors and supporting fast, accurate control loops without external accelerators.

Opting for the GE IC697CPM925-BB provides a straightforward path to enhanced computational power in Series 90-70 systems, ensuring consistent performance for applications that demand floating-point accuracy and high-speed execution. Its 64 MHz processor and dedicated FPU deliver fast scan times even with math-heavy logic, reducing cycle delays and improving process quality in precision-dependent operations. This capability helps avoid the inefficiencies of software workarounds or add-on modules, lowering engineering time and potential points of failure.

From a maintenance standpoint, the module simplifies diagnostics with clear LED feedback and accessible fault tables, allowing quick identification of issues like memory errors or power anomalies. Battery-backed memory preserves programs during outages, and the keyswitch/memory protect features reduce accidental changes during operation. Over decades of service in installed bases, this CPU has proven its durability, supporting extended asset life and easier compliance with process validation requirements through reliable, repeatable control.

The GE IC697CPM925-BB is commonly deployed in industries with legacy high-performance needs, such as chemical and petrochemical processing (for reactor control and blending), power utilities (auxiliary systems and load management), and manufacturing (material handling or batch processes). In these environments, it handles continuous uptime demands under harsh conditions—electrical noise, temperature variations, or vibration—while supporting large I/O counts and fast data cycles for coordinated control. Facilities upgrading older racks without full migration often choose it to gain modern processing speeds in critical loops where floating-point math ensures tighter regulation and better product consistency.

Compatible or alternative products include:

IC697CPM925 (base or later revisions like -CC) – Updated hardware/firmware variants with similar floating-point capabilities, often as direct replacements.

IC697CPM924 – Lower-speed (32 MHz) floating-point CPU, suitable for less demanding applications or cost-sensitive upgrades.

IC697CPU772 – Mid-range integer CPU, alternative where floating-point math is not required.

IC697CPU788 – High-performance CPU with redundancy support, for applications needing hot-standby configurations.

IC697CPM790 – TMR CPU for safety-critical systems, upgrade path when fault tolerance is prioritized.

IC697BEM731 – Genius Bus Controller, complementary module for expanded I/O in large networks.

IC697CMM742 – Ethernet interface, add-on for modern network connectivity alongside this CPU.

Before installing the GE IC697CPM925-BB, verify rack compatibility (standard IC697 chassis with adequate power supply rails) and ensure forced-air cooling meets requirements (typically 70 CFM fan for enclosed cabinets) to maintain performance above ambient limits. Check battery condition and replace if needed for memory retention, then confirm firmware/program compatibility with your application—load via serial or parallel programmer and align with Logicmaster/VersaPro versions. Inspect the keyswitch position and use memory protect during commissioning to prevent unintended overwrites.

Ongoing maintenance includes routine LED monitoring during inspections to catch faults early (e.g., CPU OK, RUN mode indicators), periodic battery checks/replacements every 5–10 years, and connector inspections for corrosion in aggressive atmospheres. Use programming software to review fault tables and clear non-critical entries, and apply any available firmware updates from Emerson during planned maintenance windows to address resolved issues or enhance stability. These steps help sustain reliable operation over long service intervals.