Allen-Bradley 1203-GD2 Serial Communication Module

The Allen-Bradley 1203-GD2 Serial Communications Module is a SCANport-compatible interface that provides RS-232, RS-422, and RS-485 serial connectivity for Allen-Bradley AC drives and related devices. It supports DF1 and DH485 framing for serial communications, enabling reliable data exchange between PLCs, drives, and other serial-equipped equipment over the module’s serial interface. Supported baud rates span 110, 300, 600, 1200, 2400, 4800, 9600, and 19200 bps, with data integrity protected by a checksum option of BCC or CRC. Powering and mounting configurations vary by style: open-style units are typically powered by the drive, while enclosed styles accept 85–264 V AC (115/230 V) or 24 V DC, depending on the enclosure, with open-style dimensions of about 45 mm (width) × 76 mm (height) × 123 mm (depth) (1.8 × 3.0 × 4.8 in.). The module’s serial side connects to the SCANport peripheral interface, acting as a bridge between serial devices and the drive’s control network. Typical applications include integrating serial peripherals such as printers, HMIs, or sensors with Allen-Bradley drives (including Flex/1336 families) to enable DF1/DH485 communications over RS-232 or RS-422/RS-485 networks. Built for industrial environments, the 1203-GD2 is designed for panel-mount or drive-mounted installations and offers a rugged solution for legacy serial connectivity in automation projects requiring direct serial interfacing to AC drives.