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Ultimate RV Electrical System Protection – Hughes Autoformer & Power Watchdog

Ultimate RV Electrical System Protection – Hughes Autoformer & Power Watchdog

It’s time to start Phase 2 of our big RV Battery & Electrical Upgrade Project by installing the ultimate protection for our RV’s electrical system: a Hughes Autoformer & Power Watchdog. A massive solar upgrade will be the main event this time around, but first we’ll focus on protecting our entire electrical system and all of our sensitive gear.

Thanks to all of the fine companies that are participating in this project for providing the expertise, equipment and service required to get this big job done.

UPDATE! Amazon prices for Hughes can sometimes be lower. Check here!

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Sunday 6th of December 2020

Hello fellow Geekers! I have been following you for many years, and am thankful for many of the upgrades I have installed, do to your excellent videos.. many thanks!?

I have an earlier model Autoformer I installed back when you first promoted it. Fortunately, I already wired it the way you show, for installing the new Watchdog.. which I just received.

Huges does not address the installation of the Whatchdog in RV’s that already have an Autoformer; their instructions do not point out that the Watchdog needs to be plugged in After the Autoformer. After watching your video again, I see why that needs to be done.. but it also brings up the safety issue of testing the power supply Before plugging ones RV into it.

Do you plan to unplug the Watchdog and use it to test a power service before you plug your extension cord into it? Seems like a pain to have to go through that every time.. but otherwise, you are plugging your Autoformer in without protection...

Appreciate your input.. and you might put in a word with Huges re instructions with the Watchdogs: without your video, I would never had known about that critical installation detail..!


Monday 7th of December 2020

Hi Steve,

Sorry for the delayed reply, we were confirming some things with Hughes before answering (and thanks for the heads-up on the manual... we've passed that info along).

As for our process with the Autoformer & Watchdog... we don't re-arrange anything when we connect to power. We leave the Autoformer in place, first in line. Then the Watchdog. The Autoformer has most (though not all) of the protections that the Watchdog has. And the ones it doesn't have, the Watchdog should pick up on, even with the Autoformer between it and the pedestal. So our Autoformer IS at greater risk of damage than if the arrangement were reversed (pedestal --> Watchdog --> Autoformer --> RV), but as you mentioned, our arrangement (pedestal --> Autoformer --> Watchdog --> RV) ensures that the Autoformer can boost low power that the Watchdog would have just shut off.

Of the wiring issues that the Autoformer could be exposed to (that it doesn't check for itself: reverse polarity, open circuit and mis-wiring), mis-wiring is the biggest potential hazard, but mostly for a 50-Amp connection that was wired as 1 x 240V instead of 2 x 120V legs. For reverse polarity/open circuit, the Watchdog would throw an alert and we should be able to turn off the pedestal power before any damage was done to the Autoformer. The 240V? THAT would likely damage the Autoformer... but it's a risk we're willing to take... especially since we have the components wired in in a way that would allow us to remove the now-fried Autoformer from the circuit so we could still function (in a different site that was tested first, of course)!

Unfortunately, there's no easy way to protect yourself 100%. If you're concerned about the risk to the Autoformer, you could try reversing its position in the circuit so the Watchdog protected it... and see if you run into any/many situations where the Watchdog shut off for low/high voltage that could have been boosted by the Autoformer.


Sunday 4th of August 2019

Hey RV geeks: You may be aware but, if not, I wanted to make you aware of apparent changes in Fire Code requirements that may put a abrupt end to the AtuoFormer products that you have endorsed. TechnoRV just today (08-04-2019) published the following information in their monthly news email:

"The National Fire Protection Agency (NFPA) has announced a change in the 2020 code that could affect how you connect your RV to power. Do you use an autotransformer/voltage regulator? These devices are designed to increase the voltage to your RV should the voltage drop on your power pedestal. These units convert amps into volts to accomplish this, and this process is now being stated to have ill-effects on surrounding power supplies. The committee for the NFPA wrote this, “The use of autotransformers places severe additional stress to surrounding electrical infrastructure not accounted for in the load calculations in this section. Park operators report that low voltage conditions typically exist when surrounding sites use these add-on devices.”

In a move to lead the way for this change in the code, Surge Guard has immediately discontinued their autotransformer models (10175 & 10176 Voltage Regulators). We have never sold these units at TechnoRV, so it will not affect anything we have sold in the past. There are other autotransformer companies on the market that will be affected by this change. I am not sure what the plan is from the other companies to conform with this new code, but I would guess that this will create change pretty quickly. image

If you currently use an autotransformer, then I would suggest that you follow the news closely on this. I am not sure how quickly RV parks will start enforcing the new regulations, but I am guessing that you will start to see a move to this in 2020."

Kim Francoeur

Tuesday 7th of April 2020

I found a switch in one of my storage compartments and I have no idea what it is. I have looked everywhere, it’s not in the useless owners manual and the dealer pretty much dropped my 1st RV off and just left after a hasty walk through. I can send a picture but don’t know how to do that in this forum! Help! Thank you! Kimberly


Sunday 4th of August 2019

Hi Dave. Thanks for the note. We’re well aware of this, but need to stress a critical part of this story that certain component manufacturers and retailers are eager to gloss over: this is a PROPOSED rule change. They continue to talk about it as though it’s a done deal, largely because it was spearheaded by, and would benefit, those very companies if it passed. We happen to know that the odds of it passing are anything but assured, and quite likely very low, despite lobbying by those same companies. We will of course stay on top of the situation as it evolves.

Loel Hofmann

Sunday 23rd of June 2019

Hi guys. We've been following you for about 18 months and recently bought a new to us 2005 Safari Cheetah DP. Now we are doing the necessary upgrades before we hit the road. I have been researching surge/EMS systems and were between the Surge Guard and Progressive. I just this morning found a reference to your review of the Bulldog and watched it. Now I am leaning towards it. I have two questions that I hope will help me make a final decision. 1) Hughes' 2 year warranty vs SG and PI lifetime warranty? On its face their's would seem the better choice. Why did you go with Hughes. Please don't sa its because they are your sponsor as we have always looked to RVG for unbiased guidance.

2) You may have covered this in the video and I missed it but why did you switch from a hardwire to portable system since Hughes makes both?

Look forward to your reply.

Loel Hofmann

Sunday 23rd of June 2019

Hi Guys- and thank for both a quick and through response. My comment on Hughes being a sponsor was meant as a joke but I guess that did not come across in writing. I always have the greatest respect for your integrity. Your points are very though provoking. Having a short term limit budget (still need to replace 6 tires before using this RV) in order of priority would you suggest buying the Autoformer or Bulldog as the first move with the other in about 6 months?

If I might pass you a tip, using dialectic grease on the plugs makes for better contact, ease of removal and prevents against corrosion for all electrical contacts, especially those that are exposed to the elements. We live currently on the water and every contact, including light bulbs, switches and outlets, etc get a coat of DEG to ensure the best contacts.

Loel Hofmann

Sunday 23rd of June 2019

If I may ask one more related question; The current Hughes Autoformer has built-in surge protection but not BT (as I understand it. If you have the current model autoformer the addition of the Bulldog EMS only adds BT app capability. Is this correct?

Steve St.Martin

Tuesday 18th of June 2019

I have the Hughes Autoformer now I'm going to have to buy another gadget LOL


Tuesday 18th of June 2019

Sorry about that, Steve! We've been told we have a habit of spending other people's money before! ?


Friday 14th of June 2019

Thanks will check it out. Pat

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