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4wsd9r b&b logo

Universal Converter

US Prices
CDN Prices

Privacy and Security Policy

General Product Information

Universal Converter - RS-232 to RS-422 4-Wire, RS-232 to RS-485 2-Wire, RS-232 to RS-485 4-Wire Compact and Easy-To-Use!

Uses Port-Power or External Power. Model 4WSD9R is three different converters in a single package. Whether you need to convert RS-232 to 4-wire RS-422, 2-wire RS-485 or 4-wire RS-485, this converter can do them all!

Simple dip switch selection of modes. Operates port- powered or with a 12VDC power supply. Using our bitwise enable circuitry ensures a fast turn around time at any baud rate without changing parts. Compact, just 3.0 x 1.6 x 0.8 in (7.8 x 4.3 x 2.0 cm) . DB9 female connectors on both sides. The RS-422 pin-outs of this unit match a SMPTE (video standard) compatible controlling device. Using RS-422 Connections to Extend RS-232

Features and Details

  • RS-232 to RS-422, RS-485 2-Wire, or RS-485 4-Wire
  • DB9 Female on RS-232 Side
  • DB9 Female on RS-422/485 Side
  • Supprts RS-232 TD and RD
  • Port Powered or Externally Powered using optional power supply
  • Data rates up to 115.2 Kbps
  • FCC Class A
  • CE


Power Range AC: 0 to 0 Temp Range: 0 to 70
Mounting / Packaging: In Line UL: No
Class 1 Division 2: No Modbus: Yes
Automatic Send Data Control: Yes Power Range DC: 12 to 12
Power Source: Port, External Power Max AC: No
RS-232: No RS-422: No
RS-485 2 Wire: Yes RS-485 4 Wire: Yes
TTL: No Current Loop: No
Multi-mode Fiber: No Single Mode Fiber: No
Isolation: No 3-Way Isolation: No
Brand: B&B Electronics  

Buy 4WSD9R on-line:
USA Office

Address: 1480 Gulf Road, Suite 837,
PO Box 1364
Point Roberts, WA 98281

Western Canada - Vancouver BC

Tel:1.800.663.6001 or 1.604.925.6150
Address: 2454 Haywood Ave
West Vancouver, BC V7V 1Y1

Eastern Canada - Markham, Ontario

Tel:1.800.465.0164 or 1.905.513.7027