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  1. RV Surge Protectors
  2. Hughes Autoformers
  3. 30 Amp
  4. Surge Protector
  5. Hardwired
  6. Bluetooth
  7. Emergency Shut Down
Power Watchdog Surge Protector with Bluetooth and Emergency Shut Down - Hardwired - 30 Amp

Power Watchdog Surge Protector with Bluetooth and Emergency Shut Down - Hardwired - 30 Amp

Item # HU77FR
Our Price: $238.14
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RV Surge Protectors
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Get on-board protection from power surges and low voltage with this hardwired surge protector. Disconnects power when voltage is low to keep your appliances safe. Monitor your connection and diagnose problems with your smartphone. Great Prices for the best rv surge protectors from Hughes Autoformers. Power Watchdog Surge Protector with Bluetooth and Emergency Shut Down - Hardwired - 30 Amp part number HU77FR can be ordered online at or call 1-800-940-8924 for expert service.
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Hughes Autoformers RV Surge Protectors - HU77FR

  • 30 Amp
  • Surge Protector
  • Hardwired
  • Bluetooth
  • Emergency Shut Down
  • Hughes Autoformers
  • 3000 Joules

Get on-board protection from power surges and low voltage with this hardwired surge protector. Disconnects power when voltage is low to keep your appliances safe. Monitor your connection and diagnose problems with your smartphone.


  • 30-Amp surge protector prevents damage to your RV from power spikes and sustained high or low voltage
  • 4-Second start-up delay gets you up and running faster than other brands
    • Delay makes sure power is safe to use before flowing normally
    • Audible click tells you the surge protector is on
  • Surge protection module offers 3,000 joules of protection in case of lightning strike
    • Can be replaced once it wears out - no need to replace the entire unit
  • Emergency Power Off cuts connection in the event of an error to protect electronics and appliances
    • Shuts down if current drops below 104V or raises above 132V
    • Also cuts power for an open ground, open neutral, reverse polarity, open circuit, or mis-wired connections
    • Automatically turns back on once power is stable for 90 seconds
  • Free Smartphone app for iOS and Android connects via Bluetooth to monitor your system
    • Quickly pair using the QR code on front of device
    • Read volts, amps, and watts in real time to keep an eye on your power draw
    • Get push notification when voltage is outside of acceptable, customizable ranges
  • Easy-to-see indicators show you if there's a problem and what that problem is
    • Watchdog logo illuminates white if power is steady and red if there's an error
    • Error code can be compared to legend on the side of the unit
  • Hardwired installation inside your RV
    • Removes the extra steps of using a portable unit at a park power pedestal
    • Protects the unit from the elements
  • ETL listed


  • Dimensions: 5-1/2" long x 4" wide x 10-9/16" tall
  • Amps: 30 amps
  • Energy dissipation: 3,000 joules
  • Limited lifetime warranty

Protect your investment

If you aren't using a surge protector, you're taking a big risk. While spikes caused by lightning can damage your electrical system and appliances, there are common electrical issues that can be just as dangerous. Choosing a surge protector with advanced features will help you protect your RV.

Smart Surge Protection

Electrical problems are not uncommon at campgrounds, especially ones where wiring was originally installed decades ago. When a campground is full on a hot day and everyone is running their air conditioners, low voltage may cause a brown-out situation and damage your RV appliances. On the flip side, faulty transmission, bad wiring, or spikes caused by other RVers connecting to a shared line can all lead to voltage issues that may not be significant enough to trip a basic surge protector.

Power Watchdog surge protectors with Emergency Power Off are equipped with computers that monitor voltage and disconnect when voltage is at risky levels. Plus, they automatically reconnect power when power returns to normal. This keeps your RV safe from problems caused by low voltage like motors overheating in fans and air conditioners.

In the event of a major spike, you can replace the surge protection module itself rather than the entire unit. The modules are plugged in without soldering, so you don't need to be an expert electrician to make an easy repair. In fact, the only tool you need is a screwdriver.

Information at Hand

The Power WatchDog smartphone app

The Power Watchdog app lets you connect to your surge protector via Bluetooth. You can monitor your energy usage, making it easy to diagnose any ongoing energy issues you may be experiencing. When voltage increases or decreases to risky levels, you will be notified right away. You can also reset your surge protector without stepping outside.

PWD30EPOH Power Watchdog Surge Protector with Bluetooth and Emergency Shut-Off - 30 Amp - Hardwired - EMS

Replaces PWD30-EPO-H

Installation Details HU77FR Installation instructionsAlternate Instructions HU77FR Installation instructions

Customer Satisfaction Score:

Customer Reviews

Power Watchdog Surge Protector with Bluetooth and Emergency Shut Down - Hardwired - 30 Amp - HU77FR

Average Customer Rating:  4.8 out of 5 stars   (911 Customer Reviews)

Get on-board protection from power surges and low voltage with this hardwired surge protector. Disconnects power when voltage is low to keep your appliances safe. Monitor your connection and diagnose problems with your smartphone.


Really tossed around if I wanted the adaptor cable or the hardwire. But glad I went hardwire. Install was easy. Can’t wait to monitor our campgrounds on my phone and protect our camper.


Wired up and functioning properly. Word of warning choose your location wisely, it has a slight hum when operating. I had to do some soundproofing in addition to the installation.



So my concerns about the slight hum were overboard. My wife very keen hearing hasnt mentioned anything about it. With the matress in place its nonexistent. The Surge protection has warned me twice of reversed polarity issues. The Bluetooth connection is worth every penny. I like to see the power consumption as we are using the camper and have a pretty good feeling for the max load where ever we hook up. I will continue to highly recommend this product and if we ever change campers you can bet Ill have another one ready to wire in on the replacement.


This surge protector hums very loudly, you could hear it inside the trailer as well as outside. I had to remove it since it made sleeping in the trailer impossible. Neither etrailer nor the manufacturer would replace it or give me a refund.

Etrailer Expert

Katrina B.


I have gotten information back from the manufacturer and they say that typically, you should not hear it from more than 5-6 feet from it, or at least it not being loud at that point. If the humming is too loud past that 5-6 foot radius, this item does have a lifetime limited warranty.


After multiple trips we have never experienced a problem with this product.


Since installing this thing I’m lucky if I can run my A/C and microwave at the same time because of the damn emergency shutdown feature. Would not recommend or purchase again.

Etrailer Expert

Brooke M.


something to keep in mind is that you would need to be wary of thing like a water heater or a battery charger could be kicking on therefore adding to the amp draw. Just double checking in keeping the total amp draw in mind is key. If those extra things kick on at the same time, that would cause it to use the emergency shutdown.


I really like this unit. All the other reviews are correct: Yes its huge, yes the bulldog logo is super bright. I installed it in an enclosed area on my trailer (Coachman Apex Nano 194BHS) in the water heater compartment (above/away from any possible water leaks), so the size and brightness are not an issue for me.

The Bluetooth range is really good (maybe too good, it reaches halfway thru the house when parked outside). The app is also pretty cool, because you can use it like a Kill-a-Watt by going around the camper turning things on/off (pro-tip: use the circuit breakers for most accurate readings).

Really appreciate not worrying about this expensive gear getting stolen, or forgetting it during setup, etc. Protected from day 1.


Installed on by cargo trailer conversion. The cover seems a little flimsy but it is comparable to what was on my previous factory travel trailer.


Just love this onboard version of the Watchdog. No more worrying about my expensive piece of equipment hanging out in the campground, lit up for all to see. Also has protected me a few times from overloading and from a faulty ground at one camp.


The unit works as advertised allowing me to see power usage on individual systems. Being able to see input voltage is good and so far, no huge power spikes.


Been working great let’s me know if I am close to a over load and if park power in correct.


The Watchdog has taken the guess work out of hooking my RV.


Fast shipping! Easy install on my keystone passport. So far so good. I like this surge protector because it is hard wired inside the rv and eliminates theft of the unit.


Easy installation


Excellent product that has likely paid for itself several times. Would purchase again


promp service thanks




I got my new Watch Dog surge protector right away, thanks George and the rest of you at trailer. A loose connection maybe to blame for replacing my old yeller one, but after 6 years it was time to upgrade to something better and I chose this because of all the videos and magazines and the Quartzsite rv show. I chose etrailer because of the customer service has always be great for me, thanks again everyone.


Just received the Watchdog Surge Protector yesterday afternoon. Plugged it in and seems to be working fine. Have yet to load the app but I anticipate no problem in doing so. Etrailer has been excellent in their communication and service.


Power Watchdog works as advertised. I love the Bluetooth connection to my phone that indicates power consumption. Installation was a breeze, other than the 50 Amp motorhome wire that is a tad stiff. Instructions were very clear.


I use this surge protector on our 5th wheel. The BT capability allows me to monitor power usage remotely and ensure my trailer is protected.


I wanted to add a surge protector with the emergency shut down after my Hughes Autoformer and this worked great. I chose this one since it had plug ends and could be easily disconnected if there were ever to be a problem with a in my electical compartment.


Received the Watchdog in the specified time window . Took it camping the next day . It is plugged in and doing its job well as I type . Seems to be a great product !!!!
etrailer has once again provided excellent communication and customer service.


Love this protector, does exactly what it needs to do: PROTECT! This last summer we took a 4th month trip in our RV and ran into a lot of sketchy power posts, luckily this protector kept our RV safe. Heavy? Yes. Hard to store as the cable is vey stiff? Yes. Would I still use 100% of the time? YES!


No worries about power surges, even during nasty Michigan storms. This product is the gold standard as the best protection for all motor home/motor Coach/trailer power feeds.

Show More Reviews

See what our Experts say about this Hughes Autoformers RV Surge Protectors

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    The Hughes Autoformers Voltage Booster with Surge Protection part # HU24FR and Power Watchdog Surge Protector with Bluetooth and Emergency Shut Down part # HU77FR are designed for trailers but so long as you don't try to pull more than 30 amp through them it would not be an issue to use them on a home with generator. The booster is basically a step up transformer, that will boost voltage 2% all the time, and if/when your voltage is low 113V or lower, it will go to a 10% boost. The watchdog...
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  • Can Power Watchdog Surge Protector # HU77FR be Used with Transfer Switch
    Yes, you can use the Power Watchdog Surge Protector # HU77FR with a transfer switch like what you mentioned.
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  • Recommended Hardwired Surge Protector
    Yes, we do have something that will protect your Airstream Travel Trailer. Depending on whether or not you have a 30 amp or 50 amp system you will want one of the following parts. 30 Amp System - Power Watchdog Surge Protector with Bluetooth and Emergency Shut Down item # HU77FR 50 Amp System - Power Watchdog Surge Protector with Bluetooth and Emergency Shut Down item # HU27FR These are hardwired surge protectors that prevent damage to your RV from power spikes and sustained high or...
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  • Are Replacement Surge Modules Available For Hughes Autoformers Power Watchdog Surge Protectors
    The Surge Modules for Hughes Autoformers Power Watchdog surge protectors are available but they are specific so to each model so you'll want ensure that you're getting the correct one. The # HU58FR is compatible with the portable # HU87FR and hardwired # HU27FR 50 amp surge protectors. The # HU38FR is compatible with the portable # HU47FR 50 amp surge protector. The # HU98FR is compatible with the portable # HU67FR and hardwired # HU77FR 30 amp surge protectors. The # HU48FR is compatible...
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    If the Portable Power Watchdog Surge Protector # HU87FR was limiting the voltage running to your RV then it's most likely a bad control module and you'll need the Replacement Surge Module for Power Watchdog Surge Protector with Emergency Shut Down # HU58FR. These modules are model specific so you'll want to ensure you're purchasing the correct one for your model. I've listed the modules and their compatible systems below incase you have a different one. The # HU38FR fits the # HU47FR The...
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  • Does 50 Amp Surge Protector Offer More Protection than 30 Amp Surge Protector?
    The Hughes Autoformers are certainly the deluxe of all the power protection products. On top of all the low-voltage, high-voltage, Mis-wiring protections they offer - the hardwired units offer protection from thieves! This unit goes inside your coach instead of hanging from the outdoor post. However, buying a 50-amp unit offers no more protection than a 30-amp unit IF your coach or trailer only connects to 30-amps. If your camper only plugs into 30 amp then you should purchase the...
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    The Redarc DC to DC Battery Charger # 331-BCDC1225D has a built in battery isolator. You will not need to add on an additional smart isolator. You are right it would be overkill, since your trailer is already set up with that functionality.
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  • How Does Hardwired Power Watchdo Surge Protector Test without RV Connected if Hardwired
    You could switch off your RV's breaker box so that when you plug in to the RV power source the Hardwired Power Watchdog Surge Protector with Bluetooth and Emergency Shut Down # HU77FR could get a reading without risking running any power your RV.
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Condition: Like New

Notes: May have damaged packaging or minor cosmetic blemishes.

Our Price: $222.95
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Info for this part was:

Employee Jameson C
Expert Research:
Jameson C
Employee Mary K
Written by:
Mary K
Employee Wilson B
Updated by:
Wilson B
Employee Cody B
Updated by:
Cody B
Employee Manda E
Updated by:
Manda E
Employee Amanda M
Edited by:
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Employee Michael B
Installed by:
Michael B

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