B&B Electronics CL03 RS-232 to Current Loop Converter

The B&B Electronics CL03 is a passive RS-232 to 20mA current loop converter designed for reliable serial data communication in industrial environments. It allows standard RS-232 serial devices to interface with legacy equipment and systems that use 20mA current loop signaling — a robust transmission standard widely used in industrial automation, point-of-sale terminals, and teletype applications.

Key Features:

• Converts RS-232 signals to 20mA current loop and vice versa
• Passive design — draws power directly from the RS-232 control lines, no external power supply required
• Compatible with standard DB-9 or DB-25 RS-232 serial ports
• Supports full-duplex serial communication
• Compact, inline form factor for easy installation
• Industrial-grade construction for reliable operation in demanding environments
• No software drivers required — fully transparent to the host system

The CL03 is an ideal solution for integrating modern computers and serial devices with older current loop-based equipment, extending the life of legacy systems without costly upgrades. Its passive, plug-and-play design makes installation straightforward with no configuration needed.