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Plugging house in generator on the coach

Hey Friends
Has anyone ever set up their coach so they could plug in their home if needed using the generator?

??
James and Suzi
1999 U320  36, Cummins M11
Build 5544  Motorcade #17268
Ronan, Montana
2020 Jeep gladiator

Re: Plugging house in generator on the coach

Reply #1 –
The original owner of our coach had PowerTech in Florida do the coach side of things for this purpose.

Generator...240 V

You must ABSOLUTELY ensure an idiot-proof transfer switch is installed where the power goes into the house wiring to prevent backfeeding power down the utility line and killing a lineman!!!!

We have no intention of using ours in this manner, but we do have a whole-house backup NG generator.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Plugging house in generator on the coach

Reply #2 –
Great practical question. Anyone with a coach parked near their house is missing out if they cannot use coach generator for long term, safe, emergency generator. This is something that needs advanced planning and can be a life saver if city power is out. Some have added a female 50-amp Buddy Plug wired to a breaker on main panel so other coaches and homes can be powered from their coach in an emergency. After turning off house main breaker, use a dangerous, illegal, correctly-wired double male 50-amp/240-volt cable hooked up between Buddy Plug and a 50-amp/240-volt house electric dryer, etc wall outlet. Or rewire home with legal, 200-amp (or whatever the house main breaker amps is) transfer switch, with an outside female 50-amp outlet matching coach input. Then use coach shore cable in reverse direction from coach to house if coach does not use an electric reel. For reel coaches, use a 50-amp/240-volt extension cable, which we should all carry. Use short power cable to match house female outlet to extension. With out a motorhome nearby, all of this planning can be used with a standalone generator, but storing gasoline for generator is very dangerous.

Re: Plugging house in generator on the coach

Reply #3 –
The big problem I see is we have two legs of 110 with our coaches not 220 so that would be a
problem in hooking up with a 220 plug in the house.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Plugging house in generator on the coach

Reply #4 –
ANY TIME YOU "BACKFEED" YOUR HOME ELECTRICAL SYSTEM, YOU MUST TURN OFF THE MAIN SUPPLY BREAKER !!!!!
As for my Motorhome set up, the 10 K generator only produces 120 volts across two legs. I do not think (as it is wired) it can produce 240 volts.  Systems designed to power homes in an emergency have automatic transfer switches to disable backfeed into the commercial supply system. 
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Gerry & Brenda
CHARLOTTE HARBOR, FL
1994 Grand Villa - # 4466
U300 Unihome - 6V92 Detroit
4 speed Allison - Jake Brake

Re: Plugging house in generator on the coach

Reply #5 –
Quote from: Gold Nugget finder –
Hey Friends
Has anyone ever set up their coach so they could plug in their home if needed using the generator?

??

Edited :
Unless someone rewired  the winding connections on your generator, it only outputs two legs at 120v. I have not heard of Foretravel wiring for 240v output on your model and year coach.

If you know how to connect it to your house correctly then you could power some of your 120 appliances and lights with the coach generator. 
 
Justin & Cathy Byrd
1995 U280 "Old Faithful"
36' Build #4673
C8.3 Cummins
Allison MD3060R 6 speed - retarder
Powertech 10KW  4cyl Kubota

Re: Plugging house in generator on the coach

Reply #6 –
You have two 120 volt legs on your home service, the red and the black, each opposite phase from the other. Your PT coach generator can be easily wired to put out 240V and the best way would be to use a 30 amp plug just like most generators you purchase at HD or HF so the cord you buy will work on the coach or portable generator.

The extension cords are not expensive on ebay. I also bought a pigtail adapter so I can plug that into the end of the 240V cord and get 120V plugs for other stuff.

We have PG&E utilities. You have read how many people they have killed and the thousands of homes they have burned. Our home service is always going out so not knowing where our RV might be, I purchased a low time CalTrans light tower trailer/generator and wired it for 240/120. I paid $1900 for it. Nice German 3 cylinder diesel. I run an extension from the generator to a transfer box next to the main panel.

As posted above, you do need an idiot proof transfer switch. There are basically two types plus automatic or manual. The first type is cheap, simple and transfers the entire generator to the house. Second is better but costs more. It allows you to select which circuits you want to power and from which leg. You can select a couple of 220V switches so you can power your well pump. It's best to select fairly equal loads for each leg as that way, it will not overload one leg of the generator. Anyway, these transfer switches don't allow you to shock anyone working on a pole. The house power cannot be energized unless the switch is moved to the "house" position.

Glad to post photos of the generator outlet plug, the extension cord and the transfer switch with the part numbers. A homeowner can install it but it does need some planning. Best to hire an electrician as you don't want to make a mistake. Lots of videos on how to do it on YouTube.

Don't put an extension cord into a house 220 outlet and hope you remember to go to your main panel and turn the main breaker off!

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Plugging house in generator on the coach

Reply #7 –
If you chose to wire your generator output leads in series for 240v output, be sure to get it right or you will let the smoke out of it. The voltage regulator leads have to be connected correctly.
Justin & Cathy Byrd
1995 U280 "Old Faithful"
36' Build #4673
C8.3 Cummins
Allison MD3060R 6 speed - retarder
Powertech 10KW  4cyl Kubota

Re: Plugging house in generator on the coach

Reply #8 –
Quote from: FourTravelers –
If you chose to wire your generator output leads in series for 240v output, be sure to get it right or you will let the smoke out of it. The voltage regulator leads have to be connected correctly.
You are not wiring them together but sending two 110/120 volt legs/wires to the house and each one to an alternating connection on the main breaker panel. So, the two different phase 120V wires NEVER touch each other or there will be trouble. In other words, there is never a single wire with 220/240V. This guy explains it well: https://www.youtube.com/watch?v=LZbIJZe_YDs

Now to explain 3 phase. (joke)

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Plugging house in generator on the coach

Reply #9 –
Our generator doesn't put out 240 volts, both 120v legs are "in phase" so there is no potential between them. The stator windings have to be wired in series to get 240v as they are connected in parallel they only produce 120v.
If you need to run 240v appliances in your home you would have to change the generator wiring.
Justin & Cathy Byrd
1995 U280 "Old Faithful"
36' Build #4673
C8.3 Cummins
Allison MD3060R 6 speed - retarder
Powertech 10KW  4cyl Kubota

Re: Plugging house in generator on the coach

Reply #10 –
Yes, were you to wire two 120 VAC hots instead of one 240 VAC (YES two hots 180 degrees "out of phase) the only things that would not work are those things that work on 240 VAC. 

This includes important things like central air conditioning, electric stove, electric dryer, etc.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Plugging house in generator on the coach

Reply #11 –
This shows our generator wiring connections.
Justin & Cathy Byrd
1995 U280 "Old Faithful"
36' Build #4673
C8.3 Cummins
Allison MD3060R 6 speed - retarder
Powertech 10KW  4cyl Kubota

Re: Plugging house in generator on the coach

Reply #12 –
I ran out of time to try to change the wiring on the PowerTech and the Genie 4000 light tower was advertised only a couple of hours away. Before I bought it, I looked up the schematic to make sure it would not be a problem. After bring it home, it was easy to identify the wires and just wire them to my new outlet plug. I needed the 220V as our well pump and mini-split are both 220V.

My question is if others have been able to change the PT wiring to get 240V from it why as it seems from above, is this not possible in this instance. Or, you could use a pair of 120V 1:1 isolation transformers but that would be expensive.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Plugging house in generator on the coach

Reply #13 –
My plan with the last hurricane was to just run a heavy extension cord in to keep the fridge going if needed.  It would be nice to wire in a transfer switch and plug for the house. My parents did this and the electrician put a separate breaker box/switch panel and wired only some circuits to be able to run off the generator.  This keeps the house side separate from the generator side so there is no backfeeding.
1991 U300 Side Aisle 6V92 Silver #3897
2004 U320 40' #6246

Re: Plugging house in generator on the coach

Reply #14 –
Some time back I had a conversation with Jeff at powertech about re wiring my generator to 240v. He recommended not doing it. Also with respect to the Motor home it was designed as a 120v wired system as far as the generator is concerned. In theory it could over load the neutral due to unbalanced electrical loads. Where as in a home the loads would be more balanced IE: 240 loads, so no issues.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: Plugging house in generator on the coach

Reply #15 –
Quote from: Pierce & Gaylie Stewart –
I ran out of time to try to change the wiring on the PowerTech and the Genie 4000 light tower was advertised only a couple of hours away. Before I bought it, I looked up the schematic to make sure it would not be a problem. After bring it home, it was easy to identify the wires and just wire them to my new outlet plug. I needed the 220V as our well pump and mini-split are both 220V.

My question is if others have been able to change the PT wiring to get 240V from it why as it seems from above, is this not possible in this instance. Or, you could use a pair of 120V 1:1 isolation transformers but that would be expensive.

Pierce

It is entirely possible to get the generator output changed to 120/240v or "split phase" as it is sometimes called. Swapping the "T" leads in the j-box isn't the problem. Correctly connecting the voltage regulator is the part you must get correct.
The old style regulator is no longer available according to Power Tech. The new regulator that is suggested to use is  wired differently, so to be safe a call to Jeff at power tech is a wise idea. He can walk you through the proper wiring changes necessary.

There are some advantages and disadvantages to doing this tho. Having a 240v output can be an advantage. The disadvantage is proper load balance is required to maintain  voltage stability. Thus the reason for Foretravel opting to use only a 120v output as there was no need for 240v in the coach.
Justin & Cathy Byrd
1995 U280 "Old Faithful"
36' Build #4673
C8.3 Cummins
Allison MD3060R 6 speed - retarder
Powertech 10KW  4cyl Kubota

Re: Plugging house in generator on the coach

Reply #16 –
Quote from: bbeane –
Also with respect to the Motor home it was designed as a 120v wired system as far as the generator is concerned. In theory it could over load the neutral due to unbalanced electrical loads. Where as in a home the loads would be more balanced IE: 240 loads.

Yes, the neutral conductor in our coaches with 120v only output carries the "sum" of the L1 & L2 loads instead of the "difference" as in a 120/240v system.
 The neutral wire should be sized larger but they are not.
Justin & Cathy Byrd
1995 U280 "Old Faithful"
36' Build #4673
C8.3 Cummins
Allison MD3060R 6 speed - retarder
Powertech 10KW  4cyl Kubota
 

Re: Plugging house in generator on the coach

Reply #17 –
If the powers out, we just step into the coach. The freezer will be fine for the first 24.  The coach has everything we need minus W/D and we have clothes for weeks....  And we rarely park it with less than 100 gal of diesel so water would be the first issue and the pool has a thousand gallons (estimated) of that.
Robert and Susan
 1995 36' 280 WTBI 8.3 3060r
 1200 watts on the roof, 720 Ah of lithium's
 Build # 4637. Motorcade # 17599
        FMCA  # 451505
        18  Wrangler JLUR