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Multi-mode Fiber Converter RS-232/422/485

US Prices
CDN Prices

Privacy and Security Policy

General Product Information

Any two pieces of asynchronous serial equipment can communicate at half or full duplex over two fibers at rates up to 460 kbps for RS-422/485 or 115.2 kbps for RS-232 with a pair of these converters. Fiber lines are inherently resistant to EMI/RFI and transient surges, so they are ideal for data communications near heavy electrical equipment and other electrical or radio interference.

Standards can be mixed and matched so RS-232 devices can be connected to RS-422/485 devices, replacing a converter and isolator. When working with RS-485 signals, B&B Electronics' Automatic Send Data control eliminates the need for driver software. Serial connections are on terminal blocks; multimode fiber side has two ST connectors. Requires external power supply not included.

Transmitter light is ON in the idle state. If you need the transmitter light to be OFF in the idle state, order model FOSTCDR-INV.

Features and Details

  • RS-232/422/485 to Multi-mode Fiber
  • Wide temperature ranges (-40 to 80º C)
  • Extend signal up to 2.5 miles
  • Modbus ASCII or RTU compatible
  • Automatic Send Data control
  • EMI/RFI and transient Immunity
  • DIN rail mount
  • UL Recognized
  • FCC Class A
  • CE


Power Range AC: 0 to 0 Temp Range: -40 to 80
Mounting / Packaging: DIN UL: Yes
Class 1 Division 2: No Modbus: Yes
Automatic Send Data Control: Yes Power Range DC: 10 to 30
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: Yes Single Mode Fiber: No
Isolation: Yes 3-Way Isolation: No
Brand: B&B Electronics  

Buy FOSTCDR 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