Your RV's electrical system is more complex than most people realize — and misunderstanding it leads to blown breakers, damaged appliances, and frustrating outages.

Here's what you actually need to know.

Your RV runs on two electrical systems:

12V DC (direct current): Powers lights, fans, water pump, slides, and most control systems. Runs from your battery bank. Works whether or not you're plugged into shore power.

120V AC (alternating current): Powers your air conditioner, microwave, electric water heater, outlets, and other high-draw appliances. Comes from shore power (the campground hookup) or your generator or inverter.

When you plug into a campground pedestal, you're connecting to the AC system. The converter in your RV also charges your batteries from shore power.

This is the question we get most often.

30 amp service:

• Single 120V leg
• Maximum 30 amps × 120V = 3,600 watts
• One AC unit, or one AC unit plus limited other appliances
• Plug: TT-30 (three-prong, one flat blade, one L-shaped blade, one round ground)

50 amp service:

• Two 120V legs (split phase)
• Maximum 50 amps × 240V = 12,000 watts (effectively two 50-amp circuits)
• Multiple AC units, electric range, and other high-draw appliances simultaneously
• Plug: 14-50 (four-prong, two flat blades, one L-shaped blade, one round ground)

If you have a large Class A motorhome or fifth wheel with two or three AC units, you need 50 amp service to run them simultaneously. On 30 amp, you'll be choosing which AC unit to run.

At Surfside Beach RV Park, every site has both 30 amp and 50 amp service available.

You will eventually arrive at a site where the available service doesn't match your rig. Adapters solve this.

50 amp rig at a 30 amp pedestal: Use a "dogbone adapter" (50F to 30M). You'll be limited to 30 amps — one AC unit at a time on a hot day.

30 amp rig at a 50 amp pedestal: Use a "dogbone adapter" (30F to 50M). Your rig will only draw what it needs — the extra capacity doesn't hurt anything.

Keep both adapters in your toolbox. You'll use them.

This is not optional. A quality surge protector or Electrical Management System (EMS) is one of the most important pieces of equipment you own.

What it protects against:

• Power surges — voltage spikes that can destroy electronics and appliances
• Low voltage — sustained low voltage (brownouts) damages motors and compressors over time
• Miswired pedestals — a pedestal with reversed polarity or an open ground can damage your rig or create a shock hazard
• Open neutral — a dangerous condition that can send 240V to 120V circuits

What to buy:

• Progressive Industries EMS-HW30C or EMS-HW50C — hardwired units that install permanently in your rig. The gold standard.
• Progressive Industries SSP-30XL or SSP-50XL — portable units that plug into the pedestal. Good option if you don't want a permanent install.
• Southwire Surge Guard — another quality brand at a slightly lower price point

Expect to pay $100–$300. It's cheap insurance against a $5,000+ appliance replacement.

On 30 amp service, you have 3,600 watts to work with. Here's what common appliances draw:

On 30 amp, running the AC plus the microwave plus the electric water heater simultaneously will trip your breaker. Stagger your high-draw appliances.

On 50 amp, you have much more headroom — but you can still overload the system if you're running everything at once.

Breaker trips repeatedly: Identify which appliance is causing it. Reduce simultaneous load. If the breaker trips with minimal load, the pedestal may be faulty — notify the park office.

Low voltage at the pedestal: Check with a voltmeter. Voltage below 108V on a 120V circuit is damaging. A quality EMS will disconnect automatically at low voltage. Notify the park office — they may be able to move you to a different pedestal.

Outlets not working: Check your rig's breaker panel and any GFCI outlets (the ones with the test/reset buttons). A tripped GFCI can knock out multiple outlets on the same circuit.

AC not cooling well: On a hot day with 30 amp service, this is often a load management issue — the AC is competing with other appliances. Switch your water heater to propane mode and avoid running the microwave while the AC is running.

Questions about electrical hookups at Surfside Beach RV Park? Call 979-233-6919 — we're happy to help.