Ci-MF11/12/21/22 Series

Modbus Plus Fiber Optic Repeater

Support 1~2 Modbus Plus bus, according to Modbus Plus Protocol
Support 1~2 Fiber Optic Ports, ST connector ( SC, FC Optional)
Support optical fiber link failure and bus error alarm output and LED indication
Support Dial switch for setting communication rate
Support Redundancy optical fiber ring network, solution cycle time<20ms
Input voltage: 9~36VDC, Dual redundant power input with 1500V high voltage isolation
IP40 protection, Metal case, 35mm DIN-Rail Mounting
Support -40~75℃ wide operating temperature range
Overview Specifications Models Resources

Overview of Modbus Plus Fiber Optic Repeater

Ci-MF11/12/21/22 series is designed for Fiber Optic Repeater which support transparent transmission for Modbus protocol. The fiber optical repeater enable electrical Modbus Plus interfaces to be converted into optical fiber interfaces. By profiting from the familiar advantages of optical transmission technology, the repeaters can be integrated into existing Modbus Plus fieldbus networks. A complete Modbus Plus network with repeaters in line, star or ring topology can be built up. It provides a fiber converter solution to extend Modbus transmission distance up to 2KM over multi-mode fiber or 20KM over single-mode fiber.


Ci-MF11/12/21/22 series supports single and dual optical daisy network. The dual fiber inputs allow connecting multiple devices in a cascade or "daisy chain" fashion for fiber redundancy. The redundant Ring enables a very high level of transmission reliability. When fiber optic error somewhere, the system will rebuild the network link within 20ms to achieve the transmission self-healing protection. This series products adopt Comark own R&D professional network protocol Ci-Ring, no need any set, no need root knot, quickly finishing the network function of ring closing and ring opening.

Ci-MF11/12/21/22 series converter provides a fiber link monitoring function to detect the communication errors on both sides of the fiber connection. When a communication error occurs, a red LED status indicator will turn on and the alarm relay contact on the terminal block will activate.

Hardware adopts fanless, low power consumption, wide temperature and voltage design and has passed rigorous industrial standard tests, which can suit for the industrial scene environment with harsh requirements for EMC. It can be widely used in various situations like industrial control, process control and traffic control.


Specifications of Modbus Plus Fiber Optic Repeater

Serial Port Interface type: DB9-F, conform to Modbus Plus protocol standard
Support Modbus Plus bus standard
Baud Rates: 1Mbps
Signal Delay (electrical interface): 7bit
Without terminal resistor, connect external when necessary

 Fiber Port

        Wave length: multi-mode 850nm/1310 nm;  single mode 1310 nm/1550nm
        Fiber type:
        multi-mode 50/125um, 62.5/125um,100/140um
        single mode 8.3/125 um, 9/125um, 10/125um
        Transmission distance: multi-mode 2km, single mode 20km
        Fiber interface type: ST/SC/FC (optional); ST (standard configuration)
        Single Fiber wavelength:
        A: Transmit wavelength is single mode 1310nm, then Receive wavelength is 1550nm
        B: Transmit wavelength is single mode 1550nm, then Receive wavelength is 1310nm
        The optical line BER: <10-9
        Signal Delay (optical interface): ≤2.3μs/node

Power Supply
DC (9~36V) dual redundant power input, industrial standard voltage DC24V
1500V high voltage isolation and reverse connect protection
5.08mm industrial terminal port
Consumption is less than 4W
      Relay: optical fiber link failure and bus error alarm output
    Contact rating: 1A @24V DC, Industrial Terminal port
      Dimensions (H×D×W): 136mm×104.8mm×52.8mm
      Weight: 800g
      Casing: IP40 protection, wave grain aluminum reinforce case option
    Installation: Wall mounting or DIN rail mounting
      Operating Temperature: -40℃~75℃(-40℃~85℃ optional)
      Storage Temperature: -40℃~85℃
    Ambient Relative Humidity: 5%~95%(non-condensing)
    5 years
      IEC61000-4-2 (ESD): Power ±2KV Contact, ±15KV Air; Relay ±2KV Contact, ±15KV Air; Data Cable ±15KV Air
      IEC61000-4-4 (EFT):Power ±4KV, Data Cable ±4KV
      IEC61000-4-5 (Surge):Power ±2KV CM/ ±1KV DM, Relay±2KV CM/ ±1KV DM
      IEC60068-2-27 (Shock)
      IEC60068-2-32 (Free Fall)
      IEC61000-6-2 (General Industrial Standard)

Models of Modbus Plus Fiber Optic Repeater

Available Models


100M Fiber Port

















  Ci-MF11/12/21/22 Series Datasheet 



 Ci-MF11/12/21/22 Series Quick Installation Guide