Hooking up house current to MH

[jlc1988]

Hi y'all. 

I'm still learning about our MH and its various features. Y'all should've seen us trying to unfurl the awning😂.  Anyway, I was curious if it is possible to hook up electricity from the house to the MH. The run from the nearest outlet to the MH is about 35'. Can you use a regular extension cord or do I need a special cord?

Thanks in advance!

[Pat & Pete]

Sure , it's possible and has been done many times . 

Using a standard extension cord will limit what you can use , electrically . 

[jlc1988]

1 minute ago, Pat & Pete said:

Sure , it's possible and has been done many times . 

Using a standard extension cord will limit what you can use , electrically . 

So no AC I assume?

[Pat & Pete]

That might be pushing it , at least at start up of the AC . That's when the highest draw of 'juice' occurs .

If you have a construction grade ( one that's built for heavy draw ) extension cord , you might be alright . 

[mysticmd]

We have an outlet on the outside of the house on its own  50  amp circuit, used for the emergency house generator, so we plug our trailer in there.   The trailer is a 50 amp service, and we use a HEAVY 50 amp cord to run from our outlet to the trailer's line, so we should be able to run everything as if we were hooked up at a site.

[Kirk W]

While you can do this, your motorhome has a power cord with a 30A plug which is configured differently than your extension cord. The first picture below is of the plug that your motorhome has.

    

The second picture is of the adapter that you will need to connect the extension cord to your motorhom'e power plug. As stated before, you will have limited power as your house outlet is probably connected to a 15a circuit breaker. In addition, you should make sure that your extension cord and the outlet that it is connected to do not overheat, as could happen.

 

[ss owens]

As far as the question of the AC, that depends on the AC and the source you plug into. Most house receptacles are attached to 15a circuits. Many RV AC units take up to 20a. Also, what else will you have connected to the same house circuit? 

If you try cranking up the AC, you stand a good chance of tripping the house breaker.

[Optimistic Paranoid]

Of course, you understand that some people hire an electrician to come in and run a separate, dedicated 30 amp circuit just for powering the motor home.  You would then use the same power cord you would use to plug in at the campground.

[Optimistic Paranoid]

BTW, you didn't actually say if your motor home has 30 amp or 50 amp service.  If the later, you have to be sure the electrician understands what you are trying to do.  The outlet box looks just like one that he's used  to using for 240 volt, not 120 volt service.  There have been some horror stories about mis-wired boxes wiping out the whole electrical system and every appliance in the motor home if wired wrong.

[mptjelgin]

Actually it is the 30 amp service that causes most of the issues. An RV 30 amp 120 volt plug looks pretty similar to a household 30 amp 240 volt plug. There have been cases where the new trailer circuit get wired for 240 volts which will immediately destroy the RV electrical system. Same thing happens when a well-meaning person "adapts" a 30 amp dryer circuit with a new outlet for the RV. 

Moral of the story: Know your plugs!!

[RV_]

Actually guys I have been reading the horror stories for bothe 30 and 50 amp RV home outlets. I put in a 30 amp outlet on my workshop sidewall which is where I park our Fifth wheel. I also ran a water line to the workshop for the RV as we were living in  it until our house was finished, almost a year due to an unexpectedly rainy summer in 2015. Our Internet provider disconnected the house and ran a cable to the RV so we had our modem and router in it with 200Mbps service for that year so all was good.

We did use a dog bone 30 amp to a regular 20 amp outside house box and extension cord and had issues in our first few months full timing in 1997 on FIL's property which we just sold. Try this for 30 amp and 50 amp wiring: http://www.myrv.us/electric/

Just click on 30 amp and 50 amp in the menus on the left .

Before you connect the RV go to the outlet testing listed on the same menu on the left of that page.  Make sure you understand it and do the tests yourself even  if you hire a professional. Those guys cause more than their share of the horror stories.

Click For Full-Size Image.

Read em and heed em and you can hook up at home too like me.

Safe Wiring!

 

[Kirk W]

4 hours ago, Optimistic Paranoid said:

BTW, you didn't actually say if your motor home has 30 amp or 50 amp service.

He did earlier tell us that he has a 1995 Southwind Storm 31H, which is a 30a RV unless someone has modified it. 

[Ray,IN]

To understand how to determine which extension cord to use, this online voltage drop calculator is invaluable. No, you will not be able to run an air conditioner from anything less than a 30A  outlet, an attempt to do so will result in either tripping the house breaker or ruining the air conditioner.

[Lou Schneider]

Don't forget to include the house wiring between the breaker panel and the outlet when using the calculator.  It will drop voltage just like an additional extension cord of the same length and gauge.

20 amp circuits use 12 gauge wire, 15 amp circuits use 14 gauge. 

[jcussen]

Not cheap, https://www.microair.net/collections/easystart-soft-starters,  but worth it if you want to keep your rv cooler on 15 amps.

[Optimistic Paranoid]

8 hours ago, Kirk Wood said:

He did earlier tell us that he has a 1995 Southwind Storm 31H, which is a 30a RV unless someone has modified it. 

Alas, Kirk, not everyone here has such an encyclopedic knowledge of motor home esoterica.

[scouserl41]

If you have an electric dryer you could always unplug it and plug your rig in there!

[jcussen]

1 hour ago, scouserl41 said:

If you have an electric dryer you could always unplug it and plug your rig in there!

Unless you have a very special dryer, not a good idea. Most dryers I have seen run on 220 volt, quick way to fry you coach. Thats why, as explained above, plugs are different.

[mptjelgin]

2 hours ago, scouserl41 said:

If you have an electric dryer you could always unplug it and plug your rig in there!

Absolutely not!!  This is a common misconception and will lead to damaging your RV. 30 amp dryer plugs are virtually all 240 volt, while 30 amp RV plugs are 120 volt. 

[scouserl41]

 

Learned something today!

 

[Kirk W]

6 hours ago, mptjelgin said:

Absolutely not!!  This is a common misconception and will lead to damaging your RV. 30 amp dryer plugs are virtually all 240 volt, while 30 amp RV plugs are 120 volt. 

 

3 hours ago, scouserl41 said:

Learned something today!

You should take a look at the two plugs and you will see that the pin configurations, while similar and enough different that unless you modify one of the two, you won't be able to connect a 30a(120V) RV to the dryer's 30a(240V) outlet.

    

[mptjelgin]

I think that the common mistake is for a well-meaning person to replace the receptacle with the RV configuration and just connecting the same three wires. Or to create an adapter by doing the same thing. Neither works...

[RV_]

Guys,

Just get a Harbor freight cheapo under ten buck Volt Ohm Meter. For measuring voltages, as long as you set it ti read AC voltage, you can't really hurt anything by doing the tests in my picture above before you plug in. Do it on your dryer outlet first and see that it is not as the chart shows it must be to plug into your RV. And unless you touch the metal part of voltage probes you can't really hurt yourself.

You don't need to understand why as long as you get the above readings for an RV 30 amp connection. If you are afraid of using a volt Ohm meter I guarantee you know someone who will show you how to safely.

Here is a video showing the multi-meter tests and how to do them:

Remember, get a cheap Volt Ohm meter and check every pedestal at RV parks before plugging in. I ran into one dangerous one of many in 7 years of RVing full time. But that was found!

Safe Travels!

[mscans]

not to sound like an ad but take a look at this company https://www.rvpoweroutlet.com/ .  besides buying the right outlet for your needs they have a fair amount of info on the site.   also be sure that you do any wiring correctly and safely.

[kb0zke]

Several of us have made devices that let us check the power pedestal before we plug in. Mine is a 50A tester, which consists of a short length of 50A cable and plug, an electrical box that takes two regular outlets, a pair of digital volt meters that plug into the outlets, a pair of polarity checkers that plug into the outlets, and a 240VAC neon light. The two outlets are wired so that one is on one leg of the 50A circuit and the other is on the other. Volt meter and checker plugged into each outlet. The neon light is wired across the two hot leads so that I know if the 50A circuit is actually wired properly.

When I'm on a 30A system I just use the dogbone and plug in my checker.

Note that this is only a way to check the condition of the electrical service at the time I'm ready to plug in. It does nothing to prevent over/under voltage, nor does it tell me about those conditions afterward. A hard-wired EMS would be the best for that, and I'm saving my pennies for one.