RV Web Network is reader-supported. When you purchase through our links, we may earn a commission. Learn more

How to Wire an RV Breaker Box? – Guide From Experts

Written by Stephen Ryan / Fact checked by William Turner


Do you have an RV with an old and inefficient fuse box that you want to upgrade? Installing a camper breaker box is a cinch if you know how to wire an RV breaker box. This electric device keeps your vehicle safe, especially when you’re switching from shore power to RV energy.

Most RVs require 30-amp circuit breakers, while large motorhomes need 50 amps. That’s why it would be best to learn how to wire a 30 amp RV breaker box. If you have an oversized travel trailer, you’ll need a 50-amp device.

Here’s how you can accomplish this task.

Table of Contents

Things You’ll Need for This Guide


Wiring an RV breaker box is hassle-free if you prepare the following materials and tools beforehand.

1. Materials (a 50-amp breaker and a circuit breaker box)

Most RVs require a 30-amp circuit breaker for their electrical distribution system. However, Class A motorhomes and oversized travel trailers might require a 50-amp breaker. Regardless of the circuit breaker, it would be best to get one recommended by the RV manufacturer.

An appropriate circuit breaker box is also mandatory for this project. I recommend a weatherproof unit for better protection against the elements. It would also be wise to check the metal junction box inside the breaker compartment.

Manufacturers of RV circuit breakers often provide electrical cables for their products. If yours doesn’t, it will be wise to buy the correct size wire for the breaker.

2. Tools

Completing this activity requires several tools, such as a wire stripper, drill and bits, screwdriver, and craft knife. A voltage meter can also be handy when confirming no electrical current in the system.

You’ll also need a marker for creating an outline of the breaker box on the wall. You can use this tool to spot the mounting holes for securing the breaker compartment.

Steps for Wiring an RV Breaker Box


Step 1. Decide where to place the breaker box.

  • Most RV owners recommend placing the breaker box in the old fuse box’s location to make wiring more straightforward. However, it would be best to remove the wires in the fuse box before uninstalling the compartment. I also suggest switching off the shore power to avoid electrocuting or shocking yourself.
  • Suppose you decide to install the breaker box for RV in a different location. In that case, I suggest looking for an accessible but well-protected area. You’ll want the breaker box to be safe from accidents and splashes. You can also install it outside the RV, but ensure it is weatherproof.

Place the breaker box in its preferred location and mark its outline on the wall, including the holes for fastening the compartment.

Step 2. Install the breaker box.

Open the travel trailer breaker box, and check if you can see a metal junction box. Position the breaker box on the wall and secure it with screws. Most RV owners use Size-8 fasteners, although the breaker box might already come with the hardware.

Check the breaker box’s side for a perforated circle. Punch out the circular panel to access the metal junction box. Secure the junction compartment to the wall, ensuring the hole points downward.

Step 3. Turn off the shore power or main breaker switch.

You don’t want to get the shock of your life when wiring an RV breaker box. So, check your vehicle’s wiring diagram to determine the location of the shore power switch. You should have no problems looking for it if this isn’t your first time. You can also check the breaker for its principal switch.

Loosen the fastener securing the breaker box’s dead-front panel. Remove this section and touch the leads with a voltage meter to confirm no current.

If you’re a newbie and don’t know how to use a voltage meter or multimeter, you can check out this video from Ratchets And Wrenches.

Step 4. Prepare the wirings.

  • Grab a wire and trim about six inches without cutting the three wires (red, black, and white).
  • Twist the individual cables with your fingers to make rigid pins, and trim them using wire strippers.
  • Connect the red and black wires to the breaker’s side.
  • Next, secure the white cable to a neutral bus strip carefully. Close the dead-front panel and tighten the screws.
  • Use cable clips to secure the wires, ensuring not to overtighten them. Doing so can produce strain points.

You can also check the RV breaker box wiring diagram if you’re unsure.

Step 5. Install the breaker and wiring to the breaker box.

  • Grab the wires and slip their ends through the breaker box and metal junction compartment. It will be wise to widen the casing by trimming about two inches.
  • Hold the breaker and connect the wires, ensuring proper tightening.
  • Insert the wires through the hole, ensuring none protrudes outside.
  • Secure the screws and make sure to tighten them properly.
  • Ensure alignment between the breaker and the breaker box tabs. Secure these using the accompanying hardware.
  • Complete the RV breaker box replacement by inserting the vehicle’s principal electrical cables into the electrical outlet. Close the weatherproof box to secure the plug.

I found this video from EXPLORIST Life – DIY Campers showing how to wire a camper van’s electrical panel. The steps are almost similar to wiring a breaker box.

Pro Tip: You can observe the same steps for wiring an RV AC breaker panel. Air conditioners are power-hungry appliances with a substantial energy draw. Using a single 30-amp breaker might be insufficient to run the AC and other RV devices. It would be best to install a separate breaker for the air conditioner.


Upgrading your old RV fuse box is a cinch if you know how to wire an RV breaker box. The process is as straightforward as looking for the ideal breaker panel location, securing the box to the wall, and preparing the wires. You can then make the electrical connections before you finalize the installation.

I hope you found this tutorial beneficial in giving you the confidence to wire your RV’s breaker box. I would appreciate it if you shared this article with others. You can also send me your comments or thoughts about this guide, and I’d gladly answer them.

5/5 - (3 votes)