svc -t /service/dbus-shelly-pro-3em-smartmeter haproxy, primary Z1 haproxy, secondary Z2
https://akkudoktor.net/t/shelly-pro-3em-in-victron-venus-os/15079/30
https://github.com/funkmaster86/dbus-shelly-pro-3em-smartmeter
https://forum.creationx.de/forum/index.php?thread/1144-shelly-bei-wechsel-kreuz-stromstoß-schaltung/
Kreuzschaltung Schaltplan
https://www.computerbase.de/forum/threads/smart-switch-fuer-stromstossschalter-gesucht.1964075/