Product Overview
The Allen-Bradley 1203-GD1 is a remote I/O communications module designed to serve as a direct digital interface between Allen-Bradley programmable controllers and SCANport-compatible drive products. As a member of the Bulletin 1203 series, the 1203-GD1 functions as a protocol gateway, converting SCANport device data into the Remote I/O (RIO) communication format understood by legacy Allen-Bradley control platforms. This module enables older drive systems to participate in modern control architectures without requiring complete equipment replacement, making it a valuable asset for maintaining and extending the operational life of existing automation infrastructure.
The Allen-Bradley 1203-GD1 occupies a unique position in industrial automation systems, bridging two distinct communication protocols that would otherwise remain incompatible. The module connects to SCANport products—such as the 1336 PLUS, 1336 IMPACT, and 1305 AC drives—through a dedicated 8-pin mini-DIN SCANport connection, while simultaneously linking to Remote I/O networks via a standard 3-pin connector. This dual-interface architecture allows plant engineers to integrate legacy variable frequency drives into PLC-5, SLC 500, or Logix5550 control systems without replacing the drives themselves.
Each 1203-GD1 module supports one SCANport product, meaning a dedicated module is required for every drive that needs to be connected to the Remote I/O link. The unit mounts independently on a standard DIN rail rather than occupying a slot within the PLC rack, providing installation flexibility and reducing backplane space requirements. With configurable baud rates of 57.6K, 115.2K, and 230.4K, along with selectable rack sizes ranging from 1/4 to full rack, the 1203-GD1 offers adaptable integration options for diverse control system configurations.
Technical Specifications
| Parameter Name | Parameter Value |
|---|---|
| Product Model | 1203-GD1 |
| Manufacturer | Allen-Bradley (Rockwell Automation) |
| Product Type | Remote I/O Communications Module |
| Input Voltage | 85 to 264V AC, 1-Phase |
| Input Current | 35 mA maximum |
| Input Frequency | 45 to 63 Hz |
| SCANport Load | 60 mA DC |
| Communication Interface | SCANport (8-pin mini-DIN) and Remote I/O (3-pin) |
| RIO Baud Rates | 57.6K, 115.2K, 230.4K (DIP switch selectable) |
| Rack Sizes | 1/4, 1/2, 3/4, Full |
| Operating Temperature | 0°C to 50°C (32°F to 122°F) |
| Storage Temperature | -40°C to 85°C (-40°F to 185°F) |
| Relative Humidity | 0 to 95%, non-condensing |
| Enclosure Rating | NEMA Type 1 (IP30) |
| Dimensions (H×W×D) | 76mm × 45mm × 123mm |
| Weight | Approximately 0.91 kg |
| Mounting | 35mm DIN Rail |
| Certifications | UL, CSA, CE |
Main Features and Advantages
The 1203-GD1 delivers essential protocol conversion capabilities that extend the service life of SCANport drive investments. By translating SCANport device data into Remote I/O format, this module eliminates the need to replace functioning drives solely for network compatibility reasons. The module’s independent DIN rail mounting configuration frees up valuable PLC rack slots and simplifies wiring routing in retrofit applications.
Flexible configuration options: Three DIP switch groups located at the module’s base provide comprehensive setup control, including rack address selection, baud rate configuration, and fault action behavior customization. The user-configurable fault action switches allow engineers to define how connected drives respond when communication is interrupted, supporting either fault reset or hold-last-state strategies based on application requirements. This flexibility is particularly valuable in processes where unexpected drive shutdowns could cause production losses or safety concerns.
Integrated diagnostic indicators: Five front-panel LED indicators report module health, SCANport status, Remote I/O activity, and fault conditions in real time. The Fault LED illuminates red during module faults, while green indicators confirm normal operation on the SCANport and RIO interfaces. This visual feedback enables maintenance personnel to quickly identify whether communication issues originate from the SCANport side, the Remote I/O side, or the module itself.
Datalink support: The 1203-GD1 supports SCANport datalinks, a mechanism for transferring parameter data between the controller and the connected drive product. Each enabled datalink consumes two words in the I/O image table, providing efficient data exchange for monitoring drive status, adjusting parameters, or reading diagnostic information. When combined with the module’s compatibility across the 1305, 1336, 1394, and SMC Dialog Plus product families, the 1203-GD1 offers a comprehensive solution for legacy drive integration.
