Hughes Autoformers Install

[Ronbrink]

I am aware that some owners use the Hughes Autoformers, even in combo with one of their Power Watchdog surge protectors. Although designed for easy use outside at the shore power post, they can be installed inside an RV which is what I decided to do. Without going into much detail, the Autoformers (available in 30A and 50A models) boost voltage when drops occur, as well as provide surge/spike protection. Surprisingly enough, a ‘search’ of this Forum did not show many results for these Autoformers. 

As a cost saving measure and matter of convenience, I passed on their Internal Hardwire Mounting Kit and simply made use of a new 10’ 30A RV extension cord. 

I did however, opt for their Mounting Bracket due to space limitations and ease of removal for service needs.

Upon disconnecting all power sources, I proceeded with removal of the exterior street side Furrion 30A Twist Lock male plug. Although I never experienced any problems in the past, I did find the ‘white’ neutral wire connection loose, probably from vibration. You’ve heard it before and now again, routinely check your wiring connections!

 

I then opened up the Automatic Transfer Relay and disconnected the individual wire ends of the stock 10 AWG Boat Cable. I was pleased to find my unit had the Wago Lever-Nuts wire connectors! The clamp connector was loosened and cable removed, all 24” of it. Note: I opted for the front 30A convenience plug for generator use, thus the stated ‘relay’.

The female plug end of the aforementioned 30A RV extension cord was cut off, measuring ~35” of cable length below the red plug and subsequently connected it to the Furrion Twist Lock plug. I used the removed cable to gauge how far to strip back the outer cable cover and individual wire ends. Again, pleased to find that the individual wire inserts on the Furrion were color-coded to ensure proper wiring. If you forget to position the neoprene gasket prior to connecting the wires, just know it can be ‘gently’ fitted over the Furrion’s cap and base. The mounting screws were then aligned with the gasket and hull holes for reattachment.

The installed female plug extension was laid out and connected to the remaining length of the male plug extension; the end of which was then fed into the relay to mark where to make another cut. For clarification, the cable right of the red plugs is the whip on the Autoformer, the left is the excess length to be trimmed. 

As before, the former cable was used to gauge necessary wire stripping. The cut length measured ~38” of cable below the red plug and subsequently attached to respective Wago connectors/ground. The cable clamp was then tightened and lid placed back on the relay.

 

By connecting the two red plug ends, the circuit loop is restored to the original configuration, but now longer and modular. The connected cables can now to tucked away when bypassing the Autoformer. Note: the final position and orientation of the Autoformer will differ from this pic.

The plug ends can now be disconnected from each other and connected to the Autoformer, as necessary, to bring it into play. These pics show the final position and orientation. Note: the ‘yellow’ light on the Autoformer indicates it is boosting, I have known for some time my storage facility voltage fluctuates and just another reason for this install. 

The above two pics shows a mockup of the Autoformer, which still needs to be properly mounted. I will update this post when undertaking that task.

[rferg800]

We also bought one of these. Good to know it will fit in this compartment. I was always worried about someone taking it in a campground.

[Ronbrink]

11 hours ago, rferg800 said:

We also bought one of these. Good to know it will fit in this compartment. I was always worried about someone taking it in a campground.

Exactly, number one reason many mount them inside an RV plus they’re heavy to cart around! I sized up a potential spot for mounting prior to purchase, but for best fitment had to deviate a few inches and in orientation. My original thought was to mount it directly over and a couple inches above the grounding bus bar (yellow wire grouping), but ended up simply repositioning the individual wire runs to the right (in pic) and turning the Autoformer 90°. I plan to install a couple pieces of aluminum angle for horizontal and vertical support, and mounting of the securement bracket. I will detail that process with a pending update to my post. 

[SeaDawg]

Looks nice. I would add that I don't own one, and won't ever likely  need one.

But, comments I've read on other forums is that many campground owners don't like them, so best to have it inside, and not mention the hefty price tag outside, totally available. 

Good job bringing it inside, and out of view.

[CRM]

2 hours ago, SeaDawg said:

But, comments I've read on other forums is that many campground owners don't like them, so best to have it inside, and not mention the hefty price tag outside, totally available. 

 

If they don't like them, it's because they don't know how they work. Some are under the impression that they "steal" power but what they really do is convert amperage into higher voltage in low voltage situations. If it's mounted inside there's no way they could know that you're using one anyway.

[Steph and Dud B]

1 hour ago, CRM said:

Some are under the impression that they "steal" power but what they really do is convert amperage into higher voltage in low voltage situations.

This is explained well here: https://changinglanesrv.com/hughes-autoformer/

(Electricians feel free to correct my interpretation here...) Volts: electrical potential (think water stored in a tank). Amps: flow of electrical current (think water pushed through a pipe under pressure). Watts: work done by the electricity (think a water wheel at the end of the pipe). You need both volts and amps to do any work. Volts X Amps = Watts. Low voltage in the campground means you have to use more amps to do the same work, but amps generate heat in the wiring so they're limited by circuit breakers for safety. (Our Olivers are limited to pulling a maximum of 30 amps from the campground grid.)

Even with an autoformer, you will never be able to pull amps (current) from the campground grid faster than the campground's pedestal circuit breaker will allow, so in that way you're no different than any other camper. However, in a low voltage situation, you will be able to get more usable power (watts) from that pedestal by jacking up the voltage in your trailer, so now you are potentially using more power than your non-autoformer neighbors. The power company bills the campground for the number of watts consumed per hour, so someone using an autoformer in a low voltage situation is costing the campground more power per hour than someone who isn't. However, you're still only using the amount of power (watts) you would have used if the campground grid was operating properly at the correct voltage, so you're not "stealing" anything. 

(A bigger question is, how does this affect the larger power grid? Is the campground voltage low because the utility company has less capacity than normal? If lots of campers in the campground are using autoformers could they overwhelm the entire campground grid and cause it to fail because they are using more watts than the grid is capable of supplying at that time? I assume there's a limit, correct?)

[CRM]

8 hours ago, Steph and Dud B said:

Even with an autoformer, you will never be able to pull amps (current) from the campground grid faster than the campground's pedestal circuit breaker will allow, so in that way you're no different than any other camper. However, in a low voltage situation, you will be able to get more usable power (watts) from that pedestal by jacking up the voltage in your trailer, so now you are potentially using more power than your non-autoformer neighbors. The power company bills the campground for the number of watts consumed per hour, so someone using an autoformer in a low voltage situation is costing the campground more power per hour than someone who isn't. However, you're still only using the amount of power (watts) you would have used if the campground grid was operating properly at the correct voltage, so you're not "stealing" anything. 

 

When running any inductive loads with motors such as AC or compressor fridge, you will be using the same amount of watts as someone who isn't using an autoformer whether it's in a low voltage situation or not. When running resistive loads such as a water heater you *will* draw more watts but you will be doing so for a shorter amount of time than someone who is using the same water heater in a low voltage situation. In the end you'll both consume the same amount of watt hours to heat the water and not be costing the campground any additional money. What you will be doing by using an autoformer if the campgrounds voltage is low is protecting those inductive appliances from premature failure due to running them at a lower voltage and higher amperage than they were designed for.

 

 

[Steph and Dud B]

@CRM, what is the effect on the larger grid? I can't imagine everyone could run autoformers without some measurable increased load on the grid or we'd all have them in our houses. When using one, aren't you further reducing the amount of power available to others on the grid? I'm not saying a single RV would make much difference, but there has to be a cost somewhere.

[CRM]

5 minutes ago, Steph and Dud B said:

@CRM, what is the effect on the larger grid? I can't imagine everyone could run autoformers without some measurable increased load on the grid or we'd all have them in our houses. When using one, aren't you further reducing the amount of power available to others on the grid? I'm not saying a single RV would make much difference, but there has to be a cost somewhere.

When it comes to the inductive loads, there shouldn't be any difference in the load on the campground since the watt draw at the pedestal is the same with or without an autoformer. This would change if everyone was running their electric water heaters or other resistive loads at the same time. By how much and to what effect is highly variable and would depend on the campgrounds electrical system. In the end, the same amount of watt hours would be used by each camper had the power been at the correct voltage to begin with.

Also, the autoformer shuts down at 104 volts so they won't be drawing power at all if the campground system dropped that low. I'm guessing a campground's grid would probably be more protected if everyone was using an autoformer than if nobody was. You'd have more angry people though since the power would be cutting off inside their campers instead of continuing to operate at that dangerously low voltage. In that situation I'd certainly rather loose power completely than destroy my ac or refrigerator.

 

[Ronbrink]

Thanks everyone for all of the enlightening information you shared regarding the Autoformers, much appreciated!

[Tom and Doreen]

The use of an autotransformer during periods of low line voltage will increase line current which could under certain circumstances stress components such as circuit breakers and cause additional heating of connectors and junctions especially those which may be oxidized. Not much of a problem in modern well maintained campgrounds but could be a problem in lesser capacity, poorly maintained / engineered campgrounds. 

Another explanation is here.

Quote

The argument against autotransformers is that during a brown-out if everybody reduces their usage/load then everyone will have some power. If everyone has a autotransformer and runs everything hence max load the park power system will draw too much current, then trip out and no one will have power. If only a few people have a autotransformer and draw full power, thus all the current they want, then others in the park will have further reduced voltage.

 

[Steph and Dud B]

@Tom and Doreen, that's basically what I suspected. Energy in a campground can't be magically created, only redistributed. Those with autotransformers will be able to use more during a low voltage event than those without, until the load exceeds the overall capacity of the grid.

[Coddiwomple]

We have the Progressive Industries EMS-PT30X which is supposed to protect against high and low voltage and surges.  Is there something about the Hughes Autoformer that I should know about that is better?  I understand it can be mounted inside for theft protection but I am more concerned about damaging the electronics, appliances, and equipment.  

[CRM]

4 hours ago, Tom and Doreen said:

The use of an autotransformer during periods of low line voltage will increase line current which could under certain circumstances stress components such as circuit breakers and cause additional heating of connectors and junctions especially those which may be oxidized. Not much of a problem in modern well maintained campgrounds but could be a problem in lesser capacity, poorly maintained / engineered campgrounds. 

 

This just isn't true... The Autoformer simply takes some of the available amps and boosts the voltage inside your camper to an acceptable range when it encounters a low voltage situation.  During a low voltage situation your AC and fridge will be drawing the same watts at the pedestal with or without an autoformer in the circuit. Probably less surge amps at startup since the motors will have acceptable voltage when starting.

 

[Doug S]

I m guessing that this used to be a reasonable recommendation before there were regulated loads and we still had incandescent lights. If the internal voltage was raised into what were closer to resistive loads, both the current and the power would go up. Not the usual case anymore, where we have mostly constant power loads.