length of 30 amp line

3oaks wrote:
140'? I think I would use my generator instead, if it was permissible. Or do without 120v electricity if it weren't available within 50'. (My on board cord plus one extension cord)

By always ensuring we're only running one high draw device at any given time I've never pulled any more than 20 amps total from a 30 amp campsite source - a few amps for the trailer itself and ~ 15 amps or less for whatever high draw device we may want to use at the time, be it A/C, microwave oven, water heater electric heating element, supplemental electric heater, toaster, coffee maker, hair dryer, or whatever. If I plug those numbers into the voltage drop calculator - 140 feet of 10 gauge cable, nominal source voltage of 120 vac, and a maximum 20 amp draw voltage drop is still less than 6 volts, which would only be a concern if the unloaded source voltage were much lower, say 112 vac. JMO, but it makes far more sense to me to limit total power consumption so I can reach a distant campsite power post. :)