Please let me know if this works. Someone else has already reported that the serial connection was very unstable while the SDongle was connected: it kept disconnecting. One theory of mine is that the SDongle and RS485A1/B1 pins are connected via the same path to the rest of the inverter hardware, causing interference when trying to use them both at the same time. But I’d like some more reports from people before I add a warning to the Wiki.
Fixed.