General Electric IC693TCM303 Serial Communication Module

GE IC693TCM303 is a dual-port serial communication module engineered for GE’s 90-30 PLC series, designed to bridge the 90-30 system with serial-enabled industrial devices—enabling reliable data exchange between the PLC and critical components like HMIs, SCADA systems, barcode scanners, and remote sensors. Unlike single-port communication modules, GE IC693TCM303 features two independent, configurable RS-232/RS-485 ports, allowing simultaneous communication with two separate device networks (e.g., one port for HMI, one for remote I/O) without protocol conflicts.

In industrial automation, GE IC693TCM303 acts as the “serial gateway” for the 90-30 PLC, translating PLC data into serial protocols (e.g., Modbus RTU) and vice versa. For example, in a warehouse inventory management system, GE IC693TCM303 connects a GE IC693CPU367 PLC to two devices: Port 1 (RS-232) links to a local HMI for real-time inventory monitoring, while Port 2 (RS-485) connects to 12 barcode scanners (multi-drop mode) across the warehouse floor. The module transmits scanner data (e.g., product IDs, quantities) to the PLC for inventory tracking, and sends PLC commands (e.g., “print label”) back to the scanners—all with 115200 bps speed for near-instant response.

What defines GE IC693TCM303 is its balance of flexibility and reliability: it supports 5 industry-standard protocols, adapts to RS-232/RS-485 based on distance needs, and integrates seamlessly with legacy 90-30 hardware. This makes it indispensable for retrofitting or expanding 90-30 systems in industries like logistics, manufacturing, and HVAC—where serial communication remains a cost-effective, widely compatible solution.

Detailed Parameter Table

Core advantages and technical highlights

Dual Independent Ports for Parallel Communication: GE IC693TCM303’s two configurable ports eliminate the need for multiple single-port modules, reducing backplane slot usage and simplifying network design. In a food processing plant, the module uses Port 1 (RS-232) to connect to a SCADA system (Modbus RTU Master) for process data logging, and Port 2 (RS-485) to link 8 remote temperature sensors (Modbus RTU Slave) via GE IC693PTM100CA modules. Previously, the plant used two separate communication modules—GE IC693TCM303 cut hardware costs by 40% and reduced wiring complexity by centralizing serial connections.

RS-232/RS-485 Flexibility for Distance Adaptation: Each port of GE IC693TCM303 can be configured as RS-232 (short-distance, 15m) or RS-485 (long-distance, 1200m), adapting to diverse facility layouts. In a large-scale HVAC system for a shopping mall, Port 1 (RS-232) connects the 90-30 PLC to a local HMI (5m away), while Port 2 (RS-485) links to 16 remote fan controllers (800m away in the mall’s basement). The RS-485 configuration avoids signal degradation over long distances, ensuring consistent fan speed control—something RS-232 alone could not achieve without repeaters.

Multi-Protocol Support for Device Compatibility: GE IC693TCM303 supports Modbus RTU, GE SNP, ASCII, and DF1 protocols, enabling communication with a wide range of industrial devices. A automotive parts supplier uses the module to connect its 90-30 PLC to two incompatible devices: Port 1 (Modbus RTU) communicates with a third-party barcode scanner, while Port 2 (GE SNP) links to a GE legacy HMI. This multi-protocol support eliminated the need for a protocol converter (costing (1,200), saving the supplier )6,000 annually in maintenance and replacement costs.

High-Speed Communication for Real-Time Control: With baud rates up to 115200 bps, GE IC693TCM303 ensures low-latency data transfer—critical for time-sensitive applications. In a high-speed packaging line, the module transmits product count data from a barcode scanner (RS-485, 115200 bps) to the 90-30 PLC in <10ms, allowing the PLC to adjust conveyor speed in real time. This speed reduced packaging errors by 25% compared to the previous 9600 bps module, saving $15,000 annually in wasted materials.

Typical application scenarios

GE IC693TCM303 is widely used in logistics and warehousing, such as a distribution center’s order fulfillment system. The module connects a GE IC693CPU367 PLC to two networks: Port 1 (RS-232) links to a local HMI for order tracking (displaying real-time order counts), while Port 2 (RS-485) connects 24 barcode scanners (multi-drop mode) across 3 warehouse zones. When a scanner reads a product barcode, GE IC693TCM303 sends the data to the PLC, which updates inventory records and triggers a label printer command via the same port.

During peak holiday shipping, the module handled 500+ barcode scans per minute without data loss—its 115200 bps speed and RS-485 multi-drop capability ensured no delays in order processing. The conformal coating also protected the module from dust in the warehouse, operating reliably for 3+ years without maintenance.

Another key application is industrial water treatment, where GE IC693TCM303 connects the 90-30 PLC to a SCADA system (RS-232, Modbus RTU Master) for remote monitoring and 12 chemical dosing pumps (RS-485, Modbus RTU Slave). The module transmits pump status and chemical level data to the SCADA system, and receives remote commands (e.g., “increase dosing”) from operators—enabling 24/7 unmanned operation of the treatment plant.

Installation, commissioning and maintenance instructions

Installation preparation: Before installing GE IC693TCM303, confirm compatibility with the 90-30 CPU (e.g., GE IC693CPU367) and backplane revision (rev. 2.0+). Ensure the environment meets 0°C to +60°C and 5%–95% RH (non-condensing). Required tools: torque screwdriver (0.4–0.6 N·m), wire strippers (22–18 AWG), ESD-safe gloves, multimeter, and Proficy Machine Edition v8.0+. Safety precautions: Power off the 90-30 system and apply lockout/tagout. Align GE IC693TCM303 with an empty 90-30 backplane slot, engage the connector, and secure with M3 screws (torque to 0.5 N·m).

Wiring and commissioning: Connect serial devices to the module’s terminal blocks (labeled for RS-232: TX, RX, RTS, CTS; RS-485: A, B, GND). For RS-485, install a 120Ω termination resistor at the farthest node (use GE IC693ACC310). Power on the system; use Proficy Machine Edition to detect the module and configure port settings: set Protocol (e.g., Modbus RTU Master), Baud Rate (115200 bps recommended for speed), Parity (Even), and Data/Stop Bits (8/1). Test communication by sending a Modbus RTU read command to a slave device (e.g., a temperature sensor) and verifying data reception in the PLC. Confirm flow control (if enabled) by checking RTS/CTS signals with a multimeter.

Maintenance suggestions: For daily operation, monitor GE IC693TCM303’s status LEDs (green = normal, red = communication fault, amber = port inactive) via the HMI. Every 6 months, inspect terminal block connections (retorque to 0.4 N·m) and clean the module with a dry lint-free cloth. Test communication integrity by sending a loopback test (connect TX to RX on a port) and verifying data echo. For RS-485 networks, check termination resistor continuity annually—replace if damaged. If a communication fault occurs, first check wiring and device settings; if the issue persists, use Proficy Machine Edition’s serial traffic logger to identify protocol errors. Replace GE IC693TCM303 with a GE-approved spare—third-party modules may not support all 90-30 protocols.