I am very happy with the two Siemens Versicharge units I have in my garage however the cables aren’t 30 feet long. Maybe more like 20 feet but I don’t need much cable as my chargers are in the front of the garage and I pull my cars straight in. I only need maybe 6-7 feet. I would imagine you could buy a 30 foot cable or maybe a J1772 extension cable. Just curious, why would you need one that long?
Max allowed by code is 25' so not likely to find a longer one fitted from the EVSE manufacturer.