Thursday, December 8, 2022


RV Electrical Safety: Q and A: 30- and 50-amp surge protectors


By Mike Sokol

Q&A’s from my RVelectricity Seminars:

I’m getting a lot of interesting follow-up questions from my RVelectricity Seminar attendees. Here’s a recent one.

Subject: 50-amp surge protector with 30-amp service

Q: Mike, I recently attended your training on electricity at the Hershey RV Show. I have a 2003 Fleetwood Southwind that has 30-amp service. I have a 50-amp Southwire Surge Guard surge protector. Can I use this surge protector if using the proper adapters and have my coach protected by the 50-amp surge protector, or should I have a 30-amp surge protector only.

Thanks for a response. —Tom Penna

A: Tom, what you’re asking about is the opposite of what I typically hear from readers. In most cases you have a 50-amp RV with a 50-amp Surge Protector, and you want to know if you can use a dogbone adapter to plug it into a 30-amp pedestal outlet, or would you need a second surge protector rated for 30 amps. See my illustration for how that would be hooked up.

And in that case, the answer is no, you don’t need a new surge protector, you simply match the surge protector amperage to whatever shore power your RV needs, and use the appropriate dogbone adapter to power it from a 30-amp or even 20-amp outlet. With the possible exception of nuisance tripping a 20-amp GFCI outlet from normal RV leakage currents, this works perfectly fine, and will protect your RV from all the standard pedestal fails such as open-ground, high-voltage, low-voltage, and reversed-polarity.

But you’re asking about the opposite thing. In your case you have a 30-amp shore power connector on your RV, and a 50-amp surge protector (I’m assuming from a previous RV) and want to know if you can use adapter cables to power your 30-amp RV from a 30-amp pedestal outlet with a 50-amp surge protector in the middle. While that technically should work, there are a lot of additional failure points built into your proposed hookup with all the extra dogbone adapters. If I were you, I would sell your 50-amp Surge Guard on LetGo, then purchase a new 30-amp Surge Guard unit that matches your RV power cord. That would be the cleanest way to get this done, and probably cost you little or nothing depending on how much you can sell your 50-amp protector for. Let me know how you make out.


Email me at mike (at) with your questions.

Let’s play safe out there….



Mike Sokol is an electrical and professional sound expert with 40+ years in the industry. His excellent book RV Electrical Safety is available at For more info on Mike’s qualifications as an electrical expert, click here.



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3 years ago

I don’t see any reason why a 50 amp surge protector cannot be used at the pedestal to power a 30 amp RV. Simply plug the 50 amp surge protector into the 50 amp receptacle of the pedestal then plug your 50-30 amp dog-bone into the receptacle of the surge protector and finally plug your 30 amp service cord into the 30 amp receptacle of the dog-bone. However, if your intention is to use ONLY the 30 amp receptacle of the pedestal than you are better off purchasing a 30 amp surge protector.

3 years ago

We had a water leek last summer while camping at a small county lake. It took all of our 6 bath and hand towels to soak up the mess. We spread half the towels on our sites picnic table and the other half on the table in the empty site next to us. Now it was nap time. When we woke up the towels on the table in the site next to us were gone. There was less than 15’ between the 2 tables and I was asleep in a recliner next to our table. Maybe that’s why they didn’t take all of the towels.

3 years ago

As a formally trained ET, I would not let the average “RV” tech touch anything electrical in my coach. If you pay attention, it Is not hard. Still possibly dangerous. One hand in your pocket rule. Good tools as you suggest, are really needed.