B&B Electronics 4WSD9R Universal Converter

🔌 Key Features & Specs

• Dual-channel converter: Converts one RS‑232 port (TD, RD + GND) to RS‑422 or RS‑485 (both 2‑wire half‑duplex and 4‑wire full‑duplex) via a DB9 female connector

• Automatic send-control: In RS‑485 mode, it auto‑enables the driver during transmit and disables during idle—avoiding echo without manual RTS/CTS control  

• Port‑powered or external: Pulls low current (<3 mA + load) from RS‑232 handshake/data lines, or uses an optional external 12 VDC @100 mA supply via 2.5 mm jack

• Baud rate & distance: Supports up to 115.2 kbps and extends signals up to 1,200 m (4,000 ft) at full speed

• Switch‑selectable modes: DIP switches set RS‑422 vs 485, echo on/off, and 2‑wire vs 4‑wire modes

🛠️ Typical Applications

• Industrial automation, remote telemetry, SCADA, or industrial NMEA‑0183 where long-distance serial communication is needed.

• Convenient for RS‑232 devices needing connection to RS‑422 or RS‑485 serial networks without requiring external power.