B&B Electronics CL259 RS-232 to Current Loop Converter

The B&B Electronics CL259 is a passive RS-232 to 20mA current loop converter designed for connecting serial devices that use current loop signaling to standard RS-232 equipment. This compact interface adapter is ideal for industrial environments where legacy current loop devices — such as older terminals, printers, and PLCs — need to communicate with modern RS-232 serial ports.

Key Features:

• Converts RS-232 signals to 20mA current loop and back
• Passive design — no external power supply required (powered by the RS-232 host port)
• Supports full-duplex communication
• Compact inline form factor for easy installation
• Compatible with a wide range of RS-232 serial devices and legacy current loop equipment
• Rugged construction suitable for industrial use

The CL259 is a reliable solution for maintaining connectivity between modern computer systems and legacy industrial or communications equipment that relies on 20mA current loop interfaces. Its tool-free, plug-and-play design minimizes installation time and eliminates the need for additional power adapters.