Product Overview
When a Genius I/O network goes down, every hour of downtime costs money. The IC694BEM331C from GE Fanuc / GE Intelligent Platforms keeps PACSystems RX3i systems talking to Genius I/O devices over a proven serial bus. Emerson now owns the line, and this module remains a practical, ready-to-ship answer for plants that need spares when they need them.
This is a single-slot RX3i bus controller. It handles the serial traffic between the controller rack and Genius I/O blocks, so your existing field devices stay online without a full platform migration.

Technical Specifications
Three software-selectable baud rates let you match network speed to cable length and device count. The IC694BEM331C runs at 153.6 Kbaud, 76.8 Kbaud, or 38.4 Kbaud. Each device can exchange 128 bytes of data, enough for typical discrete and analog I/O blocks.
2000 V isolation separates the bus from the backplane, which protects the controller from ground noise and transients on long cable runs. The module draws 300 mA from the 5 V DC backplane supply. A single RX3i system supports up to 8 of these modules, so large Genius networks can be segmented across multiple buses.
| Specification | Value |
|---|---|
| Bus | Genius I/O serial bus |
| Baud rate | 153.6 / 76.8 / 38.4 Kbaud, software selectable |
| Per-device data | 128 bytes |
| Isolation | 2000 V |
| Supply voltage | 5 V DC |
| Current draw | 300 mA |
| Max modules per system | 8 |
| Operating temperature | 0 to +60 °C |
| Protection rating | IP20 |
| Dimensions (H×W×D) | 145 × 34 × 140 mm |
Where It Fits in Your System
The IC694BEM331C suits plants that already run Genius I/O and want to keep it. Three scenarios come up often:
- Legacy line support. A packaging or process line still uses Genius blocks. This module lets an RX3i controller manage them without replacing field wiring.
- Network segmentation. With up to 8 modules per system, you can split a large bus into smaller segments. A fault on one segment does not take down the whole network.
- Spare stocking. When a bus controller fails, production stops. Keeping one on the shelf is cheaper than waiting on a long lead time.

Comparison at a Glance
| Option | Bus type | Isolation | Best for |
|---|---|---|---|
| IC694BEM331C | Genius I/O serial | 2000 V | Existing Genius I/O networks |
| Ethernet-based RX3i modules | Ethernet | Varies | New installations with modern I/O |
| Third-party gateways | Protocol conversion | Varies | Mixed-vendor networks |
If your field devices are Genius I/O, the IC694BEM331C is the direct fit. If you are building new, Ethernet modules may suit better. Oil AutoTech can help you compare options before you commit.
Installation and Maintenance
Mount the module in an RX3i rack and confirm the 5 V DC backplane supply can carry the added 300 mA load. Set the baud rate in software to match the rest of the bus. Keep the cabinet within the 0 to +60 °C operating range and respect the IP20 rating — this module needs a clean, dry enclosure.
For maintenance, inspect connections periodically and follow the manufacturer’s manual. No special cleaning or disassembly is required.
Availability Note
Official Emerson production status is unverified. The module is currently available in aftermarket channels as of September 2026. Please verify current lifecycle status and availability with Oil AutoTech before ordering.
FAQs
Is the IC694BEM331C still in production?
Official production status is unverified. It is available in aftermarket channels as of September 2026. Confirm current status with Oil AutoTech.
What baud rates does it support?
153.6 Kbaud, 76.8 Kbaud, and 38.4 Kbaud, all software selectable.
How many modules can one RX3i system hold?
Up to 8 bus controller modules per system.
What is the power draw?
300 mA from the 5 V DC backplane supply.
Does it work with non-GE I/O?
It is designed for the Genius I/O serial bus. For other protocols, you may need a gateway. Ask Oil AutoTech for selection help.
