pianotuna wrote:
Those campgrounds with long runs to a pedestal would be an excellent place to use an autoformer.
No doubt, but at the cost of an autoformer I'd always recommend an EMS as a
first purchase which offers protection from a
variety of power anomalies whereas an autoformer exists primarily to deal with excessively low campground voltage. Secondly, since voltage drop is a direct function of current draw simply minimizing one's total draw will reduce voltage drop and thereby often avoid EMS low voltage threshold cutoff. The key is to check the unloaded source voltage
before plugging in, monitor incoming voltage under load during your stay, and use only what you have to at any given time. I almost always pull from a 30 amp campsite drop but rarely exceed a 20 amp total draw, and most often much less than that. Worst case scenario, we might be running A/C but if my wife wants to use her hair dryer or any other high draw device we'll dial back the thermostat so the A/C compressor kicks off ... easy, and a lot less costly than an autoformer which I'd consider "nice to have", whereas an EMS is IMO a
necessity for those of us who normally camp on electric sites. I carry 140' of main service cable so even if I were to use it all and draw as much as 20 amps at any given time from an unloaded source voltage of 110 vac I'd
still be above my Progressive EMS's low voltage threshold cutoff voltage of 104 vac. This handy
Voltage Drop Calculator tells all by plugging in numbers to suit one's particular situation. An example ...
