Use motor home as emergency power for home

[Tony Lee]

I just tuen off the generator and flip off the breaker and then turn the power main back on.

Why wouldn't you want to just manually open (turn off) the 200amp main breakers prior to attaching and running the genny? Seems that would be more failsafe and positive control

Sounds a good way to kill a few linesmen/ or damage your generator if you get the sequence wrong and there is no interlocking between the mains and emergency supply switching.
Illegal too.

[hanko]

Originally Posted by tomwalt

Why wouldn't you want to just manually open (turn off) the 200amp main breakers prior to attaching and running the genny? Seems that would be more failsafe and positive control rather than an automatic xfer switch (that may get used a couple times a year). Or is the transfer switch the entry point for the genny power as well?
I’ve been thinking about this as well, but I only have a 30 Amp genny (1 leg of power). I think your 50amp genny hook-up is more complicated if you plan on using both power legs.

above is correct, just shutting offf the main is the wrong way (unsafe) way

[Mr_D]

Here the power company requires an automatic transfer switch so no power is backfed into the grid.

[wa8yxm]

This is what I did. First some background

Motor home is a Damon Intruder, but the make/model does not matter,
Generator is an Onan Emerald 5500 watt and here, it does matter.

Generator is 120 volt, has two 30 amp breakers (l-1 and L-2)

I installed 3 extra outlets in one of my storage bays, they are in an area were the odds of them ever getting wet... Are lower than the odds of the outlet beside the bed getting wet (very low)

Two of them are TT-30, the other is a twist lock , also 30 (4 wire).
The breakers feedign them are 30 amp (2, one for each TT-30)

And the wire is up to the job... and then some.

This has come in handy when camping as a couple friends had a generator failure once when we were out in the middle of nowhere (Desert) and what do you know, they were parked beside the only two live 30 amp outlets in the area... MY RV

In the house: I did an electrical upgrade (badly needed) and at the same time installed a Generator transfer panel, Now there are several options here I will cover 3 of them, indluding the one I used


I also made up a custom extension cord long enough and heavy enough.

When I came home one New Year's Eve (As an example, not the only time) and found Frosty the air-blown inflatable snowman sleeping on the job.. Down to the basement, get the big cord, plug outlet end into back of house, uncoil as I walk toward RV, unlock compartment and plug other end into outlet in "Basement" inside and get Gen-Turi back out and hook it up, back in and push buttons to start generator, confirm active and back to house basement, CLICK and I had light, CLICK the furnace came on .. Several more clicks and everything important was live.

ONE LIGHT was left on mains (It can not be transferred) I went up and turn it's switch on.. When the light came on it was time to swich back to mains.

That is using the full switch panel (multiple switches one for each circuit switched)

Another system uses two "main" breakers and an interlock device to insure only one of them is on at a time.. Way less expensive but you loose that indicator light function of the hall light described above.

you also have to remember to turn off stuff you do NOT want on the generator (240 volt cloths dryer for example)

And yet another, fairly new one, goes between your power meter and it's base.. This one is super easy to install, but again, see the downside on the interlock device (last paragraph).

Whatever you do remember this: An outlet is an Outlet, and an Inlet is an Inlet, NEVER use one for the other direction.

[Larrikin]

I am working on this project at my home in the hurricane zone in TX. First off, hire an electrician to put the transfer switch on your house. I suspect you can use both legs of power, and have the house "plug" be just that: it can send power to your RV parked in your yard if you make it a compatible 50Amp plug. With the circuit (transfer switch) open, the plug is "hot" and you could plug the RV into your home electric when parked at home.

Conversely, when you close the transfer switch, the power company is cut off, and your home circuit is dead. Now you can plug your RV generator into the home system and provide the 7500/10000 watts of power to the home circuit panel. Before powering up with the genset, you would want to go into the existing circuit box in the garage, or wherever, and shut off the high load circuits like ACs, Dryer, Electric range etc. But all the lights, ceiling fans, and 15 amp circuits in the house will be operated normally. Just manage your amp load on the generator.

I have not pulled the plate on the generator to look at the connections there, but that should not be a problem. If an electrician is needed use him here as well.

Best of all, you can pull up with 100 or 150 gallons of diesel on board and not have to fill the generator every 6 hours or so!

Also be sure you have an extension cord properly rated for the load and distance you anticipate.

[clyon51]

I've done it. Used a manual 3 position transfer switch. 1. Power Company 2. All Off 3. Generator (you can't screw up). You need to run both 120v phases (240v) from the genny to a recepticle near the transfer switch. That goes to the TS as well as in bound from power company. The TS takes care of it from there depending on position.

[jlfbatonrg]

We use the 7500 watt generator as a back up for 5 circuits in the house when we lose power for a long period of time. The 7500 watt Onan diesel generator in our coach produces two same phase 125 volt circuits. I wired a standard outdoor 120 v dual receptacle onto the side of the generator. Removing the cover on the upper left side of the generator gets you to the outlets from the generator. I separated the dual receptacles to provide 2 separate 120v outlets. I made up 2 10/3 power cords to run to the house. From the 5 breakers we needed for refrigerators, freezers, fans, a few lights, TVs, and laptop, I connected separate leads from the outlet side of the house breakers, to separate 10 and 15 amp breakers, and from the breakers to another separated dual receptacle on the carport. Common and neutral wires are connected properly through the recepatcles. When we need to use the generator, we open the main breaker and the 5 breakers in the main breaker box. This insures no crossover to the main house power. We connect the 2 extension cords to both the generator and the house, start the generator, then after the coach ems shows amperage, I throw the 5 new "house" breakers. We have had to run like this as long as 11 days with no problems. We have used this set up when necessary for the last 4 years.

[Submustang]

We move into the motorhome and run a cord to power the fridge and freezer. In Winter we run the woodstove to keep the house warm. Transfer switches and 50 amp outlets, etc etc, seems like an awful lot of engineering to solve a pretty simple problem. Warm bed, hot food and for those of that are really spoiled, sat TV in the RV until the power comes back on.

[clyon51]

Originally Posted by Submustang

Transfer switches and 50 amp outlets, etc etc, seems like an awful lot of engineering to solve a pretty simple problem.

It really depends on your location and your particular situation. As an example, we live in rural northern Michigan where the power goes out often (mostly winter) and for long periods. The house is on a hill on a lake. It's a ranch with finished walk out basement. Down there is our 240v water well, 2 friges, a freezer, washer/dryer, furnace and water heater. Upstairs is another frig and freezer.

It would be impossible to run enough extension cords just to keep heat in the house and keep a $1000 worth of food from ruining. Then still no water for a week.

For $200 and an hour or so of labor, well worth it to not be able to tell the power is out. Everyone's situation is different.

[CJ7ole]

I am surprised that those of you with a 50 amp shore power plug in (which is 240 volts) do not have a genny that produces 240 volts. Are you sure? Heck, even 2500 watt home gennys have a 240 volt outlet. My Winnie has a 7 kw genny that kicks out 240 volts. I put a 240 volt 20 amp plug in the power bay so I can jumper to my home's 20 amp 240 volt outlet in the garage. I trip my 200 amp main in the house and trip any big power users like the lawn pump and a/c, dryer and range and I am good to go. If my moho is not anywhere close (I store it in FL Dec-March), I use an old, noisy 3500 watt genny I had long before the moho. Yea, I know I need to get a legit transfer switch.

[sailorbowman]

Originally Posted by CJ7ole

I am surprised that those of you with a 50 amp shore power plug in (which is 240 volts) do not have a genny that produces 240 volts. Are you sure? Heck, even 2500 watt home gennys have a 240 volt outlet. My Winnie has a 7 kw genny that kicks out 240 volts. I put a 240 volt 20 amp plug in the power bay so I can jumper to my home's 20 amp 240 volt outlet in the garage. I trip my 200 amp main in the house and trip any big power users like the lawn pump and a/c, dryer and range and I am good to go. If my moho is not anywhere close (I store it in FL Dec-March), I use an old, noisy 3500 watt genny I had long before the moho. Yea, I know I need to get a legit transfer switch.

2002 Adventurer Onan 6.5 KVW Generator
120V Output in phase Generator
50 Amp Shore Power

I wish it was 220V, but I didn't build it. It will run everything in my home except the 220V well.

Never had a transfer switch and been fine, for over 30 years using a 5KVW generator. (Just remember to flip the house main breaker)

If I had an automatic start generator then an auto transfer switch would be necessary.

[Barlow46]

Originally Posted by CJ7ole

I am surprised that those of you with a 50 amp shore power plug in (which is 240 volts) do not have a genny that produces 240 volts. Are you sure? Heck, even 2500 watt home gennys have a 240 volt outlet. My Winnie has a 7 kw genny that kicks out 240 volts. I put a 240 volt 20 amp plug in the power bay so I can jumper to my home's 20 amp 240 volt outlet in the garage. I trip my 200 amp main in the house and trip any big power users like the lawn pump and a/c, dryer and range and I am good to go. If my moho is not anywhere close (I store it in FL Dec-March), I use an old, noisy 3500 watt genny I had long before the moho. Yea, I know I need to get a legit transfer switch.

Yes on the legit transfer switch. Your present procedure can back-feed your incoming line even with the 200amp main shut down. As I understand it, the only way to stop the back-feed to a lineman working to restore power (without a legit transfer setup) is to pull the meter where your power comes in from the street.

[sailorbowman]

If that was true then how could work be safely performed de-energized on an electrical panel (such as changing a breaker)? Flip the main breaker, good to go.

[CJ7ole]

Originally Posted by Barlow46

Yes on the legit transfer switch. Your present procedure can back-feed your incoming line even with the 200amp main shut down. As I understand it, the only way to stop the back-feed to a lineman working to restore power (without a legit transfer setup) is to pull the meter where your power comes in from the street.

Not to belabor the point, but if the main is tripped (both legs) you will not backfeed the incoming powerlines. Now if you flip the breaker and one leg fails to trip, yes, you will backfeed the lines. I presume a transfer switch is fail safe in this regard. As is pulling the meter.