GE FANUC 90-30 Ethernet Communication Module IC693CMM321-EE IC693CMM321EE

IC693CMM321-EE | GE Fanuc Series 90-30 Ethernet TCP/IP Module — 16 Server Connections / AAUI / Client-Server / COMMREQ / RS-232C / RS-485 / Rev EE

Connecting the Series 90-30 to Ethernet — What This Module Does

The IC693CMM321-EE installs into any Series 90-30 baseplate slot and becomes the Ethernet communications interface for the entire PLC system. Without this module (or an equivalent), a Series 90-30 CPU has no Ethernet connectivity.

Connection to the Ethernet LAN uses an AAUI cable from the module to an external transceiver (10BASE-T or 10BASE-2 depending on the transceiver type). This architecture was standard for Ethernet-connected industrial devices of this generation — the transceiver is a separate component that must be present for the network connection to function.

Once connected, the module handles all Ethernet communication independently of the CPU's scan cycle. The CPU programme initiates data transfers when needed but does not directly manage the network traffic.

Key Specifications

Client and Server — Two Communication Directions

The IC693CMM321-EE operates in both directions:

As a server: The module waits for incoming connections from host computers, SCADA systems, HMI panels, or other Series 90-30 PLCs acting as clients. Up to 16 simultaneous server connections are supported, meaning up to 16 separate devices can read or write PLC data concurrently. Server mode requires no ladder logic changes — the module responds to SRTP client requests automatically.

As a client: The module initiates outbound communication to another device with an Ethernet interface. This is done through the COMMREQ Function Block in the ladder programme. The programme constructs a communication request and passes it to the module via COMMREQ; the module executes the transfer and returns status information. Client mode enables PLC-to-PLC data exchange, remote I/O coordination, and programme-triggered data push to host systems.

Application Scenarios

SCADA integration: A Series 90-30 controlling a water treatment process. The IC693CMM321-EE provides the SCADA system with continuous read access to PLC registers — flow rates, valve positions, alarm states — via SRTP server connections. The PLC programme continues executing without modification; the SCADA polls the module directly.

PLC-to-PLC data exchange: Two Series 90-30 systems at adjacent production stations. One acts as client (using COMMREQ), the other as server. Production counts, mode status, and handshake signals transfer across the Ethernet link between the two PLCs without additional hardware.

Host computer data collection: A host computer running the Host Communication Toolkit periodically reads recipe parameters and production totals from the Series 90-30. The IC693CMM321-EE handles the requests while the PLC continues its normal scan without interruption.

FAQ

Q1: What is the "-EE" suffix on the IC693CMM321-EE?

The EE suffix identifies the hardware revision of this specific build. GE Fanuc used letter-pair suffixes (EE, JJ, etc.) to denote hardware revisions while maintaining the same functional specification. All revisions of the IC693CMM321 are functionally compatible — an EE revision installs and operates in the same system as a JJ revision without configuration changes.

Q2: Does the IC693CMM321-EE require an external transceiver, and what type?

Yes. The AAUI port on the module connects to an external transceiver via an AAUI cable. The transceiver type determines the physical network media: a 10BASE-T transceiver connects to a standard RJ-45 twisted-pair network; a 10BASE-2 (BNC) transceiver connects to coaxial cable. For most modern installations, a 10BASE-T transceiver is the correct choice. The transceiver is not included with the module.

Q3: How does the COMMREQ Function Block work for client communication?

COMMREQ (Communication Request) is a standard GE Fanuc Series 90-30 ladder instruction. In the ladder programme, COMMREQ is called with a Command Block structure that specifies the target device's IP address, the SRTP service requested (read or write), the PLC memory address, and the data count. The module processes the command asynchronously — COMMREQ returns a status that the programme monitors to determine when the transfer is complete or has failed.

Q4: Can two IC693CMM321-EE modules be installed in the same Series 90-30 system?

Yes. Up to two IC693CMM321-EE modules can be installed in a single Series 90-30 baseplate simultaneously. Each module operates independently with its own IP address and communication connections. This doubles the available server connections (up to 32 total) and provides redundant Ethernet connectivity options.

Q5: Is the IC693CMM321-EE compatible with Series 90-20 or Series 90 Micro PLCs?

No. The IC693CMM321-EE is specifically designed for the Series 90-30 backplane and is not compatible with the Series 90-20 or Series 90 Micro product lines. Additionally, the module cannot be used with GE Series 90-30 handheld programmers — it is not compatible with the handheld programming device.