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What Size Wire Do I Need For 30 Amp RV Service? – Detailed Guide

Writen by Tom Hank

Fact checked by Joseph Varney

what size wire do I need for 30 amp rv service

As an RVer, you have a natural desire to get on the road and explore the world. With your RV, you travel and see places. But for your utter comfort, you need power on your rig. And that’s where a 30 amp RV service comes in.

But like others who are not trained electricians, you wonder what size wire do I need for 30 amp RV service. And we have the right answer:

You need a 10 gauge wire for a 30 amp outlet. But there’s more to know about selecting the right wire and installing it. Read on!

Table of Contents

Understanding Essential Terms

Before you go ahead and buy the necessary wire for your 30 amp RV, you must familiarize yourself with the following essential terms.

  • A 30-amp RV service is a 120 Volts power outlet designed with a three-prong male cable coupled with a 30-amp breaker. The wiring process is quite easy by adhering to the color coding rule.
  • A 30-amp plug is equipped with three prongs: neutral, hot/live, and ground. It is commonly known as the RV-30. The piece is designated by the American National Standard Institute As TT-30P and TT-30R.
  • A 30-amp outlet has three slots for the three prongs.
  • 10 gauge wire is recommended for a 30 amp service. It functions at a 70-degree temperature, with a 650 Volts maximum voltage. This wire is super flexible and comes in various colors.
  • A gauge is also called American Wire gauge or AWG. It is the measurement in diameter of a wire using the AWG standard. The higher the gauge, the smaller is the size of the wire.

RV Wire Size Chart


It is crucial to find out exactly the 30 amp RV wire size for your camper in order to stay safe. The wire is where the electrical current flows, so you must have the right wire gauge that can handle the maximum amperage of your RV.

Let’s look at a general wire gauge chart for different amperage and wire sizes.

Maximum Amperage Gauge
7 18
10 16
15 14
20 12
30 10
40 8
55 6
70 4
95 2

According to the chart, a 30 amp recreational vehicle requires a 10 gauge wire to set up your camper’s power outlet.

How to Check the Wire Labels

Now that you have figured out the required wire size, you have to run to the store and buy a new 10 gauge wire. But before you rush out, learn how to read the wire labels first.

Find the gauge – To find the wire size for 30 amp RV plug, check the label of the cable wire. Look for the AWG section. The gauge of the wire will be noted there. So if you are searching for a 10 gauge wire, the label will show you “10”. Other gauges will be shown in the same way as well.

Understand the extra number – Sometimes, the gauge is not displayed only as “10” or other wire sizes. The cable label may read as “10/2” or it could be “10-2”, or other gauge numbers.

Take note that the extra number 2 implies that there are two sets of conductors or service wires inside the cable. And so if the gauge reads on “10”, then there is only one service wire in the cable.

Check for the presence of a ground wire – The third factor that you may find on the cable is either a “w/G” or simply “G”. This means that the 10 gauge size wire for 30 amp breaker contains a ground wire. However, the length of the ground wire does not affect the gauge of the wire.

Factors to Consider in Buying a 10 Gauge Wire


Since you now know how to read the cable labels of a gauge wire for 30 amp, let us proceed with the factors to consider in your purchasing decision.

Factor #1: Material

  • The most common material for a camper’s service wire is copper. Copper is the typical material, and it is what the gauge is based upon in this post.
  • However, aluminum is also another material that is also available for an RV outlet, though not as popular as its counterpart. If you prefer an aluminum material for the wire, take note that the gauge is “8” instead of “10”.

Factor #2: Length

The length of the wire depends on the distance between your outlet and your appliances.

To be on the safe side, choose a wire that can accommodate the whole length of your RV. This way, you are sure that if you rearrange your rig in the future, you never have to worry about the reach of the wire.

Factor #3: Color

Wires come in various colors, and they are indeed lovely to look at. One of the considerations that you need to think over is the color of the wire.

Remember that the wire will be exposed inside the RV, so think about the aesthetic of your rig. Black is a neutral color, but other colors can also make or break your camper’s interior design.

Why Do We Need Wires With the Right Gauge?

The right gauge of the wire for your recreational vehicle’s power service is essential.

It keeps you safe while traveling by ensuring that there is no fire hazard. Using the wrong wire gauge can cause overheating of the wire as the strong current flows. Plus, the melting of the wire is also possible if it cannot handle the electric current.


To answer your inquiry as to what size wire do I need for 30 amp RV service, it is a 10 gauge wire. Always remember that you can use this wire for a 20 amp RV, but you must never use a 10 gauge wire for a 40 or more amp camper.

We hope that you learned a lot from this post about the right size wire for a 30 amp RV outlet. Kindly share with your friends so we can spread the good word to the world. Also, leave us your comments and thoughts.

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