ComNet FDC80: Contact Closure Transmission, 8-Channel, Supervised

ComNet FDC80: Contact Closure Transmission, 8-Channel, Supervised

Product Code: CN-FDC80


The ComNet FDC80 Series contact closure transmitter and receiver units provide transmission of up to eight independent supervised or unsupervised dry switch or relay contact closures over a single optical fibre, or any two-wire RS-485 copper circuit. Microprocessor-based logic transmits the contact closure information in packets that are ordered and encoded, ensuring extremely robust and reliable transmission. Packets that are garbled, or packets out of sequence with transmission bit errors will not cause random changes of state in the FDC80R receiver unit relays. The supervising function in the FDC80T transmitter allows for the detection of short and open circuit conditions, and normally open or normally closed contact inputs are supported. System faults are displayed via LED status indicators, and user-programmable summary fault alarm contacts are triggered in the FDC80R receiver unit. The FDC80R receiver is offered in both latching and non-latching relay configurations. External series and shunt resistors are included for each of the 8 contact input channels, for contact supervision.

Product Options

Please add ‘/C’ for Conformally Coated Circuit Boards to extend board to condensation conditions – please contact us for pricing and delivery
Mounting: DIN-Rail Mounting adapter plate kit with mounting hardware – please order CN-DINBKT1

Non-latching receivers are also available

  • Transmits up to 8 independent supervised or unsupervised dry switch or relay contacts over one optical fibre, or via a 2-wire RS-485 point-to-point copper circuit
  • Microprocessor-based logic and latching relays in the receiver unit eliminate random contact closure states in the event of a loss of the link, or a loss of prime operating power
  • Tested and certified by an independent laboratory for full compliance with the environmental requirements (ambient operating temperature, mechanical shock, vibration, humidity with condensation, high-line/low-line voltage conditions and transient voltage protection) of NEMA TS-1/TS-2 and the Caltrans Specification for Traffic Signal Control Equipment
  • Indicating LEDs for monitoring power, contact closure status, and summary fault
  • Automatic resettable solid-state current limiters
  • Hot-swappable rack modules
  • Interchangeable between stand-alone or rack mount use – ComFit
  • ComNet Lifetime Warranty


9Vdc plug-in power supply, 90-264Vac, 50/60Hz included

Optical transmission distance is limited to optical loss of the fibre and any additional loss introduced by connectors, splices and patch panels. Distance can also be limited by fibre bandwidth. For 50/125?m fibre, subtract 4dB from optical power budget.

Extended transmission distances for the RS-485 interface models are possible – please contact us for details.

Product CodeDescriptionNo. of FibresFibre TypeOptical Power BudgetMax DistanceNo. of Rack Slots
CN-FDC80TM18-Channel Supervised Contact Closure Transmitter, 1310nm1Multimode‡ – 62.5/125?m16dB16km1
CN-FDC80TS18-Channel Supervised Contact Closure Transmitter, 1310nm1Singlemode‡ – 9/125?m23dB69km1
CN-FDC80T4858-Channel Supervised Contact Closure Transmitter, RS-485 Interface---457m2
CN-FDC80RM18-Channel Supervised Contact Closure Receiver, 1310nm, Latching Contacts1Multimode‡ – 62.5/125?m16dB16km2
CN-FDC80RS18-Channel Supervised Contact Closure Receiver, 1310nm, Latching Contacts1Singlemode‡ – 9/125?m23dB69km2
CN-FDC80R4858-Channel Supervised Contact Closure Transmitter, RS-485 Interface, Latching Contacts---457m2

How to order:

Simply send us a message using the quote form or contact our team direct via the details below!