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Isolated In-Line Serial Converter

US Prices
CDN Prices

Privacy and Security Policy

General Product Information

The 4WSD9OTB provides RS-232 to RS-422/RS-485 full or half-duplex conversion. 2000 V Optical Isolators protect your equipment from dangerous ground loops and surges. Data is converted in both directions, RS-232 Transmit data is converted to balanced RS-422 or RS-485 Transmit, and Received RS-422/RS-485 signals are converted to RS-232. Unlike converters which require programming hardware handshaking signals to control RS-485 or RS-422 operation, the 4WSDO9TB provides automatic control. The operating mode is set with 4 switches.

Features and Details

  • Compact In-line Package
  • Removable Terminal Blocks for RS-422/485 and Power
  • DB9F Connector for RS-232
  • 10 to 48 VDC Input Power is applied via a terminal block
  • 2000 V Optical Isolation
  • Data Rates up to 115.2 kbps
  • If you need a DB25 Connector - select model 4WSD25OTB


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: 10 to 48
Power Source: 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: Yes 3-Way Isolation: No
Brand: B&B Electronics    

Buy 4WSD9OTB 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