RV Electrical Load Calculator

Choose the hookup you are plugged into, tick the appliances you want to run at the same time, and this page converts their watts to amps, totals them per leg and tells you whether the pedestal breaker holds, is close, or trips. On a 50 amp pedestal you can assign each load to leg 1 or leg 2, because the two legs trip independently and it is common for both air conditioners to land on one. The appliance list starts with typical wattages, one of them anchored on a published air-conditioner spec and the rest labelled approximate, and every watt figure is a box you can type over from your own labels. It is for anyone who has ever tripped a campground breaker with a microwave and would like to know why.

How it works, how to use it, and what it does not cover

Every appliance you tick is converted from watts to amps at 120 volts, the nominal pedestal voltage, and the amps are summed for each leg. The page then compares each leg's total with the breaker rating for the hookup you chose. A 30 amp pedestal is a single 120 volt leg protected at 30 amps, so everything in the rig shares 30 amps and 3,600 watts. A 50 amp pedestal is a four-wire 125/250 volt receptacle delivering two separate 120 volt legs of 50 amps each; the RV's panel splits its branch circuits between them, each leg has its own 50 amp breaker and its own limit of 6,000 watts, and the 12,000 watt headline is only reachable if the loads happen to be balanced. The adapter options model a 50 amp rig on a 30 amp pedestal, where both legs are fed from the same 30 amps, and an RV plugged into a household 15 or 20 amp outlet, where the limit is the house circuit.

The verdict for each leg is OK below 80 per cent of the breaker, close between 80 and 100 per cent, and trips above 100 per cent. The 80 per cent line is the usual continuous-load rule for breakers; running above it for long periods is how they weaken and start tripping early. When a leg trips, the page names the biggest load on that leg as the one to switch off first, and shows how many amps that would free.

To use it, set the hookup, tick the realistic worst case (both air conditioners, the water heater on electric, someone making coffee while the microwave runs), and look at the leg totals rather than the grand total. On a 50 amp rig, open your breaker panel: the labels tell you which circuits are on which leg, and the calculator's default leg assignments are only a plausible split. The converter is always on; it draws little when the batteries are full and several hundred watts after a night of boondocking, which is why the breaker trips in the first hour at a new site.

What it does not cover: the RV's own branch breakers, which are usually 15 or 20 amps and will trip before the pedestal if you put a kettle and a hair dryer on the same bathroom circuit; start-up surge, which matters for generators, inverters and soft-start decisions but seldom trips a pedestal breaker; low campground voltage, which raises the current every motor draws and is the subject of our surge-protector guide; the inverter, which moves 12 volt battery energy into 120 volt loads and complicates the arithmetic when it is also charging; and propane appliances, which draw a few watts for their boards and fans and are left out. Wattages other than the air conditioner are typical figures, not measurements; a plug-in power meter replaces every one of them with a real number.

Data last verified 2026-10-28. Prices, hours and rules change; confirm with the official source before you go.