We need to separate groups of Modbus devices for electrical safety and I'm thinking use fiber optic. For this aim I'd like to use serial media converter (Fiber optic/Modbus) and create a fiber optic ring. At the beginning of each group of Modbus Devices I'd put a Converter. I'd like to know if Is possible having more than one Modbus node after a serial media converter or Is it necessary one for each node (slave)?
And If ring breaks itself in a point, the communication pass through by the other side or It's broken his too?
thanks in advance
A converter with RS485 output can have more than one device connected (multi-drop).
A device that you could use:
From it's description:
The I-2541 is an RS-232/422/485 to fiber optic converter that ensures data transmission security by using fiber optic transmission technology to provide immunity from EMI/RFI interference.
The I-2541 is designed for RS-232/422 point-to-point connections and RS-485 multi-drop applications which require a signal to be transmitted for distances of up to 2Km (6,600 ft), and is a perfect solution in applications where transmission must be protected from electrical exposure, power surges, lightning strikes or chemical corrosion.