With the AC running the outlets in my stick house read 116 volts.
It is hot in Chicagoland!
With nothing ? ON in the MH,your charger may use 15 amps when you first plug in.
Your findings sound normal to me on a weak line.
Siggy
Happy Trails
Siggy & Ursula
2011 Dutch Star 4020,ISL 400,Compr.brake,FTL XCR,IFS
Allison MH3000
2015 Jeep Cherokee,4x4 Active Drive II,V6 , Brake Buddy,Roadmaster Sterling,
Camping since 1975 Pop-Up,1986 22Ft.TT,1999 Gas MH,2005 KSDP,
2011 DSDP,FMCA 368283