My AS 27 came with its standard 25 ft 30 amp cord, which has sufficed on all but one time. The exception, would you believe it, was at the AS factory, in Jackson Center. There, I was parked next to a 30 ft Classic, which used a 50 amp cord. It turned out that both his & my parking sites used the same electrical panel. He used a 50 amp socket; I used a 30 amp socket. The problem was that my 30 amp breaker kept breaking despite however little power I was using. Consequently, I attached a 25 ft, 30 amp extension to my existing cord & plugged it in to an electrical panel a ways away. Result: Consistent, reliable power. If I hadn't had the extension, I could not have reached the other panel & would not have had power as long as my neighbor was using his 50 amp circuit on the same panel.
Alta & Richard, Seattle area --- WBCCI 8877
"Aurum": 2015 Ram 2500 Laramie 4x4 Diesel
"Argentum": 2016 AS FC 27 FB
"BigDog": M Harlequin Great Dane, 150 lb
"Megan" (aka "LittleDog"): F Shih Tzu, 15 lb
WL7Z --- NAUI --- WSBA