I think I’m correct in thinking that most house’s have a 60amp fuse (which is single phase) if you have a 100 amp fuse it means you a have 3 phase power coming into your house. You only need 3 phase if you have large motor driven devices located at your address, I think you would also need 3 phase if you wanted a 22 Kwh wall charger installed.
60 amps is adequate for the 7 Kwh wall charger.