Post subject: Mitsubishi PLC RS485 2W Communication to Weintek HMI..

We have two PLCs both are Mitsubishi-FX2N, and we want them to communicate to Weintek HMI MT8100ie.
MT8100ie can communicate with Multiple PLC and it Supports RS232 on Com1, RS485 (2W/4W) on COM1 and RS485 (2W only) on Com3.

So, we are using RS232 on COM1 for PLC1 and COM3 (RS485 2W) for PLC2.

PLC1 is successfully communicating over RS232 Com1 (after a RS422 to RS232 converter), but PLC2 is not.

What i have known Mitsubishi has RS422 default and its 4 wired. Its our limitation we cant use 4w we are left with 2w mode.

We tried different Parameters and wiring but still we are unable to get anything.

Any help / Guidance in this regard will be highly appreciated.

With the Weintek you can only choose one port or the other. If you are using RS232 that is only for a single point communication between two devices. Not only that but RS232 requires 3 wire for read write communication. The Weintek can communicate with multiple PLC's But only in the RS485 mode where each PLC is addressable.