Generators Resource

Interactive Sizing & Electrical Reference

The Two Types of RV Power Systems

If you want to buy a generator to boondock or camp off-grid in your RV, you first need to know what electrical system your camper uses. RVs come in two standard configurations: 30-Amp and 50-Amp.

But how many watts do those actually equal?

30-Amp RVs: 3,600 Watts

A 30-amp RV plug has three prongs and operates on standard 120-volt power. To find the total wattage capacity of the entire camper, we use Ohm's Law (Watts = Volts ร— Amps):

120 Volts ร— 30 Amps = 3,600 Watts

If you try to use more than 3,600 watts simultaneously in a 30-amp camper, you will trip the main breaker on the pedestal or the generator.

What Generator Do You Need for a 30-Amp RV?

A 3500-watt to 4000-watt inverter generator is the perfect match. This maxes out the RV's capacity, allowing you to run the AC unit, the microwave, and charge the batteries.

50-Amp RVs: 12,000 Watts

A 50-amp RV plug has four prongs. It operates on a 120/240-volt split-phase system. It actually provides two separate 120-volt, 50-amp legs of power.

Leg 1: 120V ร— 50A = 6,000 Watts
Leg 2: 120V ร— 50A = 6,000 Watts
Total Capacity = 12,000 Watts

This is a massive difference! A 50-amp RV has more than triple the power capacity of a 30-amp RV, allowing for dual AC units, a washer/dryer, and electric water heaters.

What Generator Do You Need for a 50-Amp RV?

To fully utilize a 50-amp RV, you would need a massive 12,000-watt generator. However, most RVers don't boondock with that much load. A 5000-watt to 7000-watt generator with a 50-amp dogbone adapter is usually sufficient to run two AC units simultaneously.

Typical RV Appliance Wattages

RV Appliance Running Watts Starting Watts
13,500 BTU Air Conditioner 1,500W 3,000W
15,000 BTU Air Conditioner 1,800W 3,500W
Microwave 1,000W 1,000W
Water Heater (Electric Mode) 1,400W 1,400W
Pro Tip: Run your RV water heater and refrigerator on propane while running off a generator. This frees up massive amounts of electrical watts for your air conditioner.