Greg Giannoni

Hi. I manage several plants with Easun inverters (mostly SMP5K, SV IV5.6 and SMW11K). Almost every plant is monitored by some ARM (mainly OP3 or NanoPi M1+) boards. On plants with 2, 3 or 4 inverters, I had many issues : usb link unstable, rs232 adapters burning, or USB hub burnings after few days or weeks. I came to the conclusion that there is a GND issue. Your conclusion looks almost the same. To avoid this issue, on SV IV5.6K, I now connect only 1 inverter, and use PGS command to query the other ones. But with SMP5K, there is no equivalent command, and I sometimes ends with 1 arm board per inverter (and sometimes, it works fine with 1 board for 3 inverters). But as you advocate to isolate more, I wonder if the inverse option could work : did you try to connect GND of displays together ? I think I'll give a try next time I'm in a plant with unstable links, but as I understand, it should make things goes better. kinds regards from Corsica, Greg.