Last year, I did yet another PV install at a friends house. While plugging the SMA inverter to the solar field (600V), I fucked up and inverted plus & minus.

Nothing happened. I read the manual and realised that SMA inverters are protected against reverse polarity. Yeah, a bit more expensive, but well worth it

I'm more surprised you managed to plug them in reversed; did you have good reason to avoid the polarized semi-pwrmanently-latching connects that most panels ship with?

Because panels are on the roof, the inverter is on the basement, so you have to run your own cables and crimp the mc4 connectors on them. If you swap them around they get mixed up ;-)