Description
🔹 Product Introduction
The GE IC697CPM790 is a Series 90-70 Central Processor Unit designed for GE PLC systems and IC66* Triple Modular Redundancy applications. It features a 64 MHz, 32-bit 80486DX2 processor with floating-point calculation capability and 1 Mbyte of battery-backed memory.
The CPM790 is a single-slot CPU and communicates with the control system through the rack backplane. It supports RS-422/RS-485-compatible serial communication and can be used with compatible GE Series 90-70 I/O and option modules.
For TMR applications, the CPM790 is intended to operate as part of a dedicated triple-modular-redundancy architecture. Ethernet programming/communication requires a compatible Ethernet interface module rather than a built-in Ethernet port on the CPU.
⚙️ Technical Datasheet
| Parameter | Specification |
|---|---|
| Brand | GE / GE Fanuc |
| Model | IC697CPM790 |
| Series | Series 90-70 |
| Product Name | Central Processor Unit |
| Processor | 80486DX2, 64 MHz, 32-bit |
| Memory | 1 Mbyte battery-backed CMOS RAM |
| Floating Point | Supported |
| Serial Interface | RS-422/RS-485 compatible |
| 5 VDC Bus Current | Approx. 3.3 A nominal |
| Operating Temperature | 0 to 60°C with 70 CFM forced air; 0 to 40°C without forced air |
| Condition / Status | New – Open Box |
🧩 Key Features
- Single-slot Series 90-70 CPU
- 64 MHz 32-bit processor
- Floating-point mathematics
- 1 Mbyte battery-backed memory
- Up to 512 Kbytes available for application program and data
- Designed for IC66* Triple Modular Redundancy systems
- RS-422/RS-485-compatible programmer serial interface
- Supports GE IC660/IC661 I/O in TMR configurations
- Supports compatible IC697 discrete and analog I/O in simplex operation
- In-system upgradeable firmware
🔧 Installation & System Integration
The IC697CPM790 is designed for installation in the appropriate Series 90-70 rack and is specified for Slot 1 installation. Before replacement, verify the rack configuration, CPU firmware, memory/battery condition, and TMR architecture.
For serial programming or communication, the CPU provides an RS-422/RS-485-compatible serial attachment. Ethernet TCP/IP programming requires a compatible Ethernet Interface module such as an IC697CMM741 or IC697CMM742.
Because the CPU uses battery-backed CMOS memory, the battery condition should be checked before commissioning or extended storage. The published specification indicates approximately six months of nominal memory retention without applied power.
🛠️ Maintenance & Troubleshooting
Battery inspection: Check the battery status before removing system power. Replace the battery according to the applicable maintenance procedure when required.
CPU diagnostics: Check the front-panel status LEDs for CPU, RUN, memory protection, and system conditions.
Communication problems: Verify the serial connection, cable configuration, communication parameters, and compatible interface hardware.
TMR applications: Confirm that the three CPU channels, associated Genius buses, I/O, and redundancy configuration are correctly matched.
Thermal management: Maintain the required airflow. The specified operating range reaches 60°C when 70 CFM forced-air cooling is provided.
❓ FAQ
Q1: What is the memory capacity of the IC697CPM790?
A: It has 1 Mbyte of battery-backed CMOS memory, with up to 512 Kbytes available for the application program and data.
Q2: What processor does the CPM790 use?
A: It uses a 64 MHz 80486DX2 32-bit processor with floating-point calculation capability.
Q3: Is the IC697CPM790 a standard Series 90-70 CPU?
A: It belongs to the Series 90-70 family but is specifically designed for IC66* Triple Modular Redundancy applications.
Q4: Does it have an Ethernet port?
A: No built-in Ethernet port is specified. Ethernet TCP/IP communication requires a compatible Ethernet interface module.
Q5: What serial interface does it use?
A: The CPU provides an RS-422/RS-485-compatible programmer serial attachment.
Q6: What is the nominal 5 V bus current?
A: The detailed CPM790 specification lists approximately 3.3 A nominal.
Q7: What cooling is required?
A: The published specification allows 0–60°C operation with 70 CFM forced-air cooling, or 0–40°C without forced air.
Q8: Is the battery important for this CPU?
A: Yes. The memory is battery-backed, so battery condition should be verified before commissioning and during maintenance.
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