Is Your Legacy Control System Losing Its Communication Edge?
Obsolete communication modules fail more often than any other component in aging control cabinets. The GE IC693CMM311 answers that problem directly. It is a communication coprocessor module built for the Series 90-30 Programmable Logic Controller platform, originally manufactured by GE Fanuc Automation and now supported under Emerson Automation. This single-slot module adds two serial ports and multi-protocol connectivity to any modular Series 90-30 CPU, restoring the data links that keep production lines visible and controllable.
What the IC693CMM311 Actually Delivers
The module carries two independent serial ports. Port 1 supports RS232. Port 2 supports RS232, RS422, and RS485 electrical standards. Both ports use 25-pin D-shell female connectors. A single connector serves both ports, so technicians use the IC693CBL305 Wye cable to separate them for easier wiring.
The module supports CCM, RTU, and SNP communication protocols. You can configure protocol combinations across the two ports, including CCM on both ports, RTU on both ports, SNP and SNP-X on both ports, or mixed combinations such as CCM on Port 1 with RTU on Port 2. Supported transmission speeds are 300, 600, 1200, 2400, 4800, 9600, and 19200 baud. A push-to-restart button re-initiates communication without restarting the entire module.
Three LED indicators report module health: Module OK, US1, and US2. These lights let maintenance staff diagnose port activity at a glance.
Technical Specifications at a Glance
| Parameter | Value |
|---|---|
| Manufacturer | GE Fanuc / Emerson Automation |
| Series | Series 90-30 |
| Product Type | Communications Coprocessor Module |
| Communication Interfaces | Port 1: RS232; Port 2: RS232 / RS422 / RS485 |
| Supported Protocols | CCM, RTU, SNP |
| Communication Cable | IC693CBL305 Wye cable |
| Bus Voltage | +5 VDC |
| Current Load | 400 mA |
| Module Width | Single slot |
| Max Modules per Baseplate | Four (4) |
| LED Indicators | Module OK, US1, US2 |
| Port Connections | 25-pin D-shell, female |
Where This Module Fits in Real Plants
Legacy Series 90-30 systems still run packaging lines, water treatment skids, and material handling equipment. When an existing communication coprocessor fails, production visibility drops immediately. The IC693CMM311 restores CCM, RTU, and SNP links to modular CPUs, keeping SCADA polling and peer-to-peer data exchange alive.
In a typical replacement scenario, a plant engineer swaps a failed module, reconnects the IC693CBL305 Wye cable, and verifies port LEDs. Because the module supports multiple protocol combinations, the same unit can serve different network segments across a facility. That flexibility reduces the number of spare part numbers a maintenance team must stock.
Installation and Setup Notes
Mount the module in any slot of a Series 90-30 CPU baseplate except the CPU slot. The module draws 400 mA from the +5 VDC backplane bus, so verify power budget before adding multiple modules. A baseplate supports up to four CMM modules when using CPU models 331 and later.
Embedded CPUs such as the 311, 313, and 323 do not support this module. Confirm your CPU is a modular type before ordering. Configuration can run through a default setup or through configuration software, depending on your network requirements.
Compatibility and Integration
The IC693CMM311 works with modular GE Series 90-30 CPUs. It does not work with embedded CPUs. Supported protocols include CCM, RTU (Modbus RTU), and SNP. The IC693CBL305 Wye cable is the compatible pre-assembled cable for separating Port 1 and Port 2 connections.
Maintenance and Reliability Guidance
Inspect the module periodically for loose connections and LED status. Clean cabinet airflow paths to prevent overheating. Because this product is discontinued, verify current lifecycle status and availability with SpareTechPLC before ordering. Stocking a spare module protects against unexpected downtime in legacy systems where replacement options are shrinking.
Selection Checklist Before You Buy
Confirm your CPU is a modular Series 90-30 model, not an embedded type. Verify you have the IC693CBL305 Wye cable or an equivalent wiring plan. Check that your baseplate has an open slot and sufficient +5 VDC current capacity. For availability and replacement guidance, contact SpareTechPLC.
Frequently Asked Questions
Does the IC693CMM311 work with embedded Series 90-30 CPUs?
No. It is compatible only with modular Series 90-30 CPUs. Embedded CPUs such as the 311, 313, and 323 do not support this module.
What protocols does this module support?
The module supports CCM, RTU, and SNP protocols. You can configure different protocol combinations on Port 1 and Port 2.
What cable do I need for the two ports?
The compatible pre-assembled cable is the IC693CBL305 Wye cable. It separates the two ports from the single 25-pin connector.
How many IC693CMM311 modules can one baseplate hold?
A CPU baseplate supports up to four CMM modules when using CPU models 331 and later.
Is the IC693CMM311 still in production?
No. The product lifecycle status is discontinued/obsolete. Contact SpareTechPLC to verify availability and replacement options.
