Now that we’ve had the coach a full year, it somehow flips a switch in my head to start making more major modifications. After 1 year I’m suddenly more comfortable drilling holes or rewiring something. Maybe it’s a subconscious realization that our warranty has expired and now it’s on ME to repair things and make them the way I want?
Hughes 50-amp Autoformer
What is a Hughes Autoformer and why do I want one?
Our 2020 newmar Dutch Star came with an all-in-one transfer switch and surge protector. I didn’t have much experience with the all-in-one units, I’ve always used a dedicated surge protector. I started to shop for an additional surge protector, and as I was reading about them in the groups and forums, I learned about an ‘autoformer’ and did some more research.
So what does an autoformer do? In the most simpliest of definitions, it attempts to provide a consistent voltage by ‘boosting’ the voltage from the pedestal as needed. Hughes has a really great Youtube video showing how it works. Basically, as the campground fills up and more and more people turn on their power hungry AC units, the voltage to your pedestal can fluctuate. When the voltage gets too low you may not be able to operate your RV’s components in the way that you expect, or you might cause damage to them by running them with too low voltage.
Yes it’s legal. No, you’re not ‘stealing power’ from the campground or anyone else. You’re still limited to the breaker on the pole – 50-amp – you’re just leveling out the voltage.
The Autoformer needs at least 90 volts coming into it. Without an Autoformer, 90 volts would likely damage some of the electrical components inside your coach.
You might be wondering what is the differences between an Autoformer and a Surge\Voltage Protector, like the Hughes Watchdog?
The Hughes Watchdog with EPO provides surge and voltage protection, shutting off power at 104 volts on the low end, 132 volts on the high end, protecting the equipment inside your coach from ‘bad’ power situations, not just a surge.
It’s important to understand your equipment and the thresholds it has and utilize them in the correct circumstances and location in the chain. If you put the Watchdog before the Autoformer, the EPO shuts off and negates the value of the Autoformer.
Overview
I’m a Product Owner for a mainframe performance monitoring software solution, so I spend my days strategizing where I see the product going, and talking with new and potential users to gather requirements. When we decide to move forward with an idea the architects take my strategy and the customer’s requirements and design a solution. I guess that has rubbed off on me…I went to Visio to create a diagram of what I wanted the system to look like based on what I wanted it to do. Knowing that I would want to ‘train’ others to be able to hook up our coach, I labeled and color coded all the components as I went.
Here’s the result:
As I was considering how I wanted to use the Hughes Autoformer and Hughes Watchdog, I took a component approach to it. How can I use or bypass the components in a failure? Reading through the various Newmar groups and forums, people have mentioned the power cord reel is a failure point (not specific to Newmar, but in general). So I thought if I were going to this trouble, I’d make the system so I could bypass it in an emergency.
I wanted the system to still be used by bypassing the Hughes Autoformer – I am hearing the use of an Autoformer is not allowed in some RV parks – and if it experiences a surge, I did not want to be out of service while awaiting the user replaceable parts to arrive.
In my design, I will add some additional plugs and outlets. While this additional wiring adds failure points, they are easily repairable in the field, and would not keep me out of service for very long.
I still have more to consider in this design. The generator goes directly to the transfer switch, and the transfer switch is the single point of failure. If it fails, and they sometimes do, I could be limited to one or no power inputs.
The diagram above outlines the components involved, from pedestal to coach, and the various configuration options. I’ll talk about them later on in this post.
Installation Process
You don’t have to do any kind of installation at all if you don’t want to, you can simply put the Autoformer at the pedestal and plug your RV into it. But, the 50-amp unit weighs about 40 pounds, and is $550+ US (at the time we purchased in 2021). While it does come with a little cable lock, I didn’t want to lug this thing in and out of the coach, have it sitting out in the elements, or be gone when I returned.
The first step is to of course buy the Autoformer that you need, 50-amp or 30-amp. Ours is a 50-amp, and after searching several options we found it cheapest at Amazon with the Prime shipping (30-amp version). We also ordered the 50-amp install kit (30-amp version) so we could hardwire the unit in the electrical bay rather than have it outside at the pedestal.
To me, there were advantages to a hardwire install.
- Better isolation of the individual power components
- If the cord reel goes bad, I can easily use an extension to bypass it
- If the Hughes Autoformer goes bad, I can bypass it
- This puts the Autoformer inside the locked coach bay, out of the weather and prying eyes
Once you’re ready to start the install, you’ll need to be disconnected from shore power and have the generator off, you’re going to be rewiring the automatic transfer switch.
Our coach has an automatic cord reel, so I started by removing that. 2 bolts in the front is all it took, as there’s a metal bracket that holds the back side. There’s a small wire that routes power to the reel, and on the other side the switch, located on the bay door, to operate the reel. Be mindful of those and the various routing clips screwed into the wall. I had to remove those as I went, but then the reel just lifted out and there was enough cord length to set it outside.
Once there was room to work, time to pop the cover off the automatic transfer switch\surge protector installed by Newmar when they built the coach. It’s held on by 2 screws and some clips, just pull the lid off once the screws are removed.
If you don’t know what the transfer switch does, it automatically switches the power source from generator (priority source) or shore power to provide a single source of power to the coach system.
Follow the wiring…there are two inputs: generator and shore power. In our unit, the shore power was the black cable in the rear, and is coming from the power reel. The front (gray cable) is coming from the generator.
Take a picture of the wiring before removing it. I also wrote the color just above it. You are removing the connections from the power reel and wiring in the plug that came with the installation kit. This is #8 in my diagram.
Using an allen wrench or socket, remove the red, white and black wires, and a flat head screwdriver to remove the green wire. Loosen the clip on the underside of the transfer switch that holds the cable in place, then remove the cable.
Route the cable from the plug that came in the kit through this same hole and secure in the same exact way. The colored wires came ready to install, but I did need to cut them a little shorter and strip them. Easy enough. With the plug installed, you’re done with the transfer switch and can close it back up.
Note: I took the opportunity to move the transfer switch up and back as much as possible to leave room for the Autoformer in the bay.
I apparently did not take a picture of the outlet I wired to the power cord reel. This is #3 in my diagram, and the light gray box on the left side of the picture, just above the Autoformer.
Once I wired the 50-amp outlet, I mounted it on the wall next to the transfer switch, and remounted the power reel. It all went together very easily.
I took this opportunity to move the cable-in jack to the top right side (from the bottom left) near the light. We rarely use it, and it was just in the way. There was plenty of cable to move it to anywhere inside this bay.
Testing the System
We’re very fortuante to have a 50-amp plug at our home, we use it all the time to cool down the coach while we are loading it (we don’t store it at home), so I was able to test it right away. And I was anxious to validate our power.
- Plug the main power cord (#2) into the power source (#1) with the power source breaker off. This would normally be the campground power.
- Plug the Autoformer (#4) into the newly wired outlet attached to the power cord reel (#3).
- Turn on the breaker at the source (#1). The Autoformer will validate that connection, ensuring it is safe.
- If it’s safe, turn off the breaker at the source.
- Plug the newly installed plug from the Transfer Switch (#8) into the Autoformer (#5). Turn on the breaker at the source. Your coach is now fully powered, safely through the Autoformer.
Adding More Layers of Protection
Now you can optionally add another layer of protection – and I highly recommend doing that!! An Autoformer will boost the voltage as needed to keep it within the safe range for the electronics in your coach, but what if there is a low or high voltage situation? Either of those are dangerous! What if you want to remotely monitor the power coming into the coach?
We chose to add a Hughes Watchdog PWD50-EPO. This extra layer of protection also provides additional functionality: Emergency Power Off, and Bluetooth connectivity for monitoring with alerts.
Per Hughes’ recommendation, we place the Watchdog between the Autoformer (#5 #6) and the coach transfer switch (#7 #8). Should the voltage drop to 104v or below, or rise to 132v or above, the EPO will shut off the power. If you put the Watchdog first, it will shut off the power if it falls too low, competely negating the value of the Autoformer. The Autoformer needs at least 90v to work, well below the lower threshold of the EPO.
What’s interesting is when I hooked up the entire system at home, connected to the 50-amp hookup, the Watchdog EPO would activate and shut off the power. I kept fiddling with it only to realize that we have such ‘clean’ power here at home that the base 2% boost by the Autoformer put the amperage too high! So I removed it from the connection and all is fine. This proves that it’s not a one-size-fits-all solution, it’s very much situational and you need to educate yourself to understand how it works, when and when not to use it.
The Huges Watchdog has a bluetooth connection to their app you can install on your phone. It lets you see the voltage and amperage per leg, in real-time. It also sends you alerts when there’s a problem and the EPO kicks in, shutting off power. The Watchdog is only bluetooth, I’d love the ability to connect it to my coach wifi/internet system so that I can get alerts when I’m out of range. This way I’d know if my ice cream is going to melt before I make it back from hiking. 😉
Summary
There is no question this is an expensive ‘upgrade’ and some would argue unnecessary since Newmar includes the built-in surge protection with the automatic transfer switch they install. Do enough research and you’ll also read about the controversy surrounding the usage of an autoformer.
For us, when looking at the cost of our 2020 Newmar Dutch Star in relation to these extra precautions, it was an easy decision. We’ve added multiple levels of protection: consistent voltage which protects our equipment, 2 additional surge protectors, and finally an EPO: Emergency Power Off should things realy go sideways. And in doing so, we’ve also ensured we can easily bypass any ‘broken’ component (except the transfer switch) to retain power to the coach.
While long-term usage will validate our decisions, I will definitely feel more confident our coach is protected along the journey.
Other Resources
Changing Lanes recently did a great write-up and YouTube video on the Hughes Autoformer. It’s well worth the read and watch! Chad explains the concept very clearly.
Note: This post contains affiliate links for products and I do receive a commission, at no additional cost to you, if you purchase using these links. Thank you for your support!
