fx3u and fx2n 485bd

[davidtofton]

I was using 2 fx2n's with parallel link using 485bd cards, one of the fx2n's stoped working properly some of the inputs went faulty, so i changed it for a fx3u and also had to change the bd card to the 3uu version. Now the 2 plc's don't communicate, i have the terminate resistor on 110 ohms as before, the plc was wiped and the original program converted. But still no Comms. Is the fx3u bd card compatible with the 2n bd card? Plc diagnostics comes back with link error, great thanks, also i/o Config err Thanks

[Inntele]

davidtofton, FX3U and FX2N can't communicate with each other using Parallel Link protocol: 1. The Parallel Link baudrate is: for FX3U series -115200 bps, for FX2N - 19200 bps 2. The parallel link operates only between PLCs of the same group. FX3U and FX2N are related to the different groups.

[Crossbow]

Inntele is right . The FX3U Communication manual JY997D16901 shows the groups that can communicate in the section on parallel link. Section C, look at chapter 3.1.

[davidtofton]

Thanks guys, It had me and a Mitsubishi technical guy busy for a few hours. Just means Mitsi sell more FX3U's

[Crossbow]

Well the big reason for the incompatibility is the change in baud rate. It's not some gimmick to sell more PLCs, it's an advancement in the communication speed. At least that's my thought, not sure if that's what they had in mind or not...