An Essential Guide：Choosing the Right RV/EV Extension Cord

As an avid RVer, I’ve had my fair share of learning experiences on the road. One of the most important lessons I learned was during my first adventure across Oregon when I discovered the hard way that I had purchased the wrong RV extension cord. I was in the Silver Spur RV Park, where the electrical setup required a 50-amp connector, but the cord I bought was only rated for 30 amps. This mistake not only caused inconvenience but also taught me the importance of understanding the nuances of RV power needs.

In this blog, I’ll share my insights on choosing the right RV extension cord, ensuring safety and answering a common question about charging electric vehicles like Tesla car with RV extension cord.

This guide is especially for RV newbies or those who have just started their RV life, helping you avoid common pitfalls and make informed decisions to enhance your travel experience.

1. How to Choose the Right Extension Cord for Your RV

Choosing the right RV extension cord isn’t just about picking the first cord you see on the shelf. Here are the key factors to consider:

1.1 According to Your RV Type

Different RVs require different amperage: 30-amp or 50-amp. Check your RV’s power specifications before purchasing. Using the wrong cord can lead to power issues or even damage your RV’s electrical system.

1.2 According to Where You Stay

• State Standards:Electrical setups can vary between states. For example, in California, many RV parks provide 50-amp connections as a standard, while in Texas, you may encounter a mix of 30-amp and 50-amp setups depending on the region. To make it easier to check the specific requirements of your destination, you can use resources like Campendium ( https://www.campendium.com/ ) or RV Parky ( https://www.rvparky.com/ ) for detailed information about RV park electrical setups across the U.S.

• RV Parks vs. Public Parking Lots vs. RV Resorts:While most RV parks offer standard 30-amp and 50-amp hookups, some public parking lots might not have these options, requiring you to use adapters or different extension cords.

1.3 According to Your Needs

When considering the distance of your RV from the power source, a longer cord may be necessary, but ensure it's appropriately rated for the amperage to prevent overheating or power loss, especially since wire lengths beyond 50ft significantly increase resistance, causing a drop from 50 amps to 40 amps.

2. Can You Charge Your EV with an RV Extension Cord?

This is a common question among RVers who also own electric vehicles like Teslas. Here’s what you need to know:

2.1 Conditions for Using an Extension Cord to Charge a Tesla Car

• The extension cord must support the amperage required by your Tesla’s charging needs. Most Tesla models charge at 32 amps or more, so a cord rated for 50 amps is generally recommended.

• The cord should be UL-certified or ETL-certified and designed to handle high power loads consistently.

2.2 Tesla’s Official Recommendation

Tesla's official website offers NEMA adapters, as shown in the Max Distance Gained Per Hour of Charge table above, but does not supply extension cords due to concerns about increased resistance and reduced efficiency.

If you must use an extension cord, they recommend selecting one rated for the required charging load and designed for continuous high-power use. The RVGUARD 50 Amp RV/EV Extension Cord is equipped with NEMA 14-50 connectors making it perfect for all your high-power charging requirements.

RVGUARD NEMA 14-50 extension cord supports fast charging, even you can use two of these together for extra length, but you need to know that for every foot of extra cord you add,there will be a voltage drop.

3. How to Ensure Your RV Extension Cord is Safe

Safety is paramount when dealing with RV extension cords. Here are some key aspects to consider: 

3.1 Check for Standards and Certifications

• UL Certification: Ensures the cord meets safety standards in the U.S., as verified by Underwriters Laboratories, a globally recognized safety organization.

• ETL Certification: Indicates compliance with North American safety standards, verified by Intertek, an equally reputable testing laboratory. Both UL and ETL certifications signify that the product has been independently tested and meets stringent safety requirements. The primary difference lies in the certifying bodies, but both hold the same credibility and assurance for safety and performance.

3.2 Inspect the Cord

• Look for durable, weather-resistant insulation.

• Ensure the cord connectors are firm and properly shielded to prevent accidental shocks.

3.3 Regular Maintenance

• Inspect your cord regularly for signs of wear and tear, such as frayed wires or damaged plugs.

• Store the cord in a dry, cool place when not in use to prevent weather damage. 

Final Thoughts

Choosing the right RV extension cord is not just about convenience; it’s about ensuring the safety of your RV’s electrical system and your personal safety on the road. Take the time to understand your RV’s needs, research the standards and certifications, and invest in a quality cord that will last.

And if you’re an electric vehicle owner, ensure the extension cord you use meets the high demands of charging systems like Tesla’s. Safe travels and happy adventuring!