Use onboard Onan to power house in emergency?

[FSAD]

So I was thinking, hey, I got a fancy schmancy Onan, built right into the camper, so why would I need to buy some portable unit to run various things in the house during an emergency?!

So I grab my 20A 50' cord, thinking I'll just fire up the genny and plug the ext cord into the outlet on the outside of the camper, run it into the house and feed a few things off a decent powerstrip with individual cords.

Then I got to thinking.... Sure that all SOUNDS like it would work, but would it? Here's why I question it.

Running a 20A cord from the "genny" to the house is good enough to power multiple other individual cords, but the outlet on the camper, I'M GUESSING, is a measly 14 ga. going back to the genny output. Hence, I would not be really running a 20A cord from the genny!

right?

So, can I tap into the genny somewhere else that I can wire up an additional outside plug on the camper that is truly heavy enough to run my ext cord that will then feed all the little other cords in the house?

I'm not an electrician (obviously, that's why I'm asking) but I have the mechanical ability to do such a mod, and believe that I COULD have an issue if I try to power too much stuff off the ext cord, since the outlet back to the genny is most likely wired with smaller gage wire, I'm sure.

thanks!

mikey

[TEXAS]

DryCamper11 wrote:

DavidM49 wrote:
It has been just my luck to have spent the money to put it in and we have not lost power yet. LOL

I purchased an old gen and rebuilt it, then added the interlock to power the home. It's the best guarantee against losing power. You never lose power once you're ready. 🙂

That is the way it works. Just like if you lose a tool. Just go buy another one and you will find the one you lost.

[FSAD]

Wow, great replies guys. This thread will live on in history!

I think I have enough info to do what I need, but if I ever go the transfer route, I'll have that info too!

Thanks again for the help, and don't worry, I won't back feed my panel and hurt anyone.

thanks again,

mikey

[DryCamper11]

DavidM49 wrote:
It has been just my luck to have spent the money to put it in and we have not lost power yet. LOL

I purchased an old gen and rebuilt it, then added the interlock to power the home. It's the best guarantee against losing power. You never lose power once you're ready. 🙂

[DavidM49]

I just had my panel replaced and had the generator interlock installed where I can power my entire home without the fear of any back feed. I have a 7500 watt Generac genset which should power everything with the exception of my AC. We lose power frequently and have slept in our camper during the summer. Like everyone else said, a basic extension cord works or have it done professionally and put the interlock in. It has been just my luck to have spent the money to put it in and we have not lost power yet. LOL

[wa8yxm]

What I recommend and what I did, are exactly the same thing, yes, I practiced what I now preach.

I had an electrician upgrade my service panel, the old Push-matic box was a pain in the operating system, or anatomy or whatever you like so we put in a brand new Square D. Much nicer, bigger too.

We also added a genuine generator transfer panel With switches (3 position switches, Main/Off/Generator) and watt meters no less (This last bit is a luxury and not really needed, but it does come in handy).

On the back of the house was an INLET 30 amp 120/240 volt Twist Lock (NOTE below)

I made up a special HD extension cord, as I recall 8GA by 70 feet or so.

Matching plug and socket

And installed a matching OUTLET in a weather protected location on the RV.

ALong with a pair of 30 amp Female pigtails I might add.

So when Frosty The Airblown Inflatable Snowman was sleeping on the job one Christmas seson (our last in the house) I went to the basement, (Windows let in light so I could see) grabbed the cord, Plugged the outlet end onto the house inlet, Uncolied as I approached the RV, plugged the plug end into the RV's outlet, went in, got the Gen-Turi and put it on, back in and pushed the needed buttons (STOP (hold it) then Start, (Tap it) then Start again) and shortly after the generator started I heard the CLUNK of the transfer switch and observed the Prosine display light up.

Back to the basement and CLICK, lights
CLICK, Furnace
CLICK freezer
CLICK Refrigerator
CLICK, Click Click, Computers, TV's and DVR's More lights and so on.

Cost of all that hardware... Oh, I had close to a kiobuck by the time I paid for the install (Transfer switch, Cord, Electricain, Stuff on the RV)

Value of warm wife... PRICELESS.

If I ever get another house.. I'll get another cord and transfer panel.

The promised note:

THe ONAN only puts out 120 volt, it puts out 120 volt at around 50 amps total in my case. It is not a 120/240 volt device, SO I can not put the Central Air COnditioner, the Electric cloths dryer or, if I were to buy one an electric range on the transfer panel.

I can, however, finish a load of wash and hang it up to dry.

[MEXICOWANDERER]

People who do not work lines will quip "Don't they check before climbing a pole?"

Of course they do. But what they CAN NOT DO is to have a physic warning system that alerts them when a homeowner is about to throw a switch that is improperly configured.

With my made it myself power transfer switches I use neon type 120 VAC indicator pilot lights. I also installed an outlet on the power company side of the transfer switch. I connect an extension cord and bright light to it and run the cord out to where I can see it from living quarters. This lets me know when power is restored.

[randallb]

If you really want dependable emergency power do it correctly. Every one is right on the money with installing a transfer switch to protect the linesmen. You can manually trip the main but then you do not know when the power comes back on unless you live in an urban area. I also recommend a propane generator. It does not care how long the fuel sits and if you are like me you will have multiple bottles (to use for back up) that are used for the gas welder, powering the shop water heater and the shop space heaters. You also do not need to power the whole house. You just need to keep the food cold, the heater running, the well pump going and a light or two. A 5500 watt generator does this nicely and the total hardware cost will be around $1100 dollars. Labor is extra but nobody dies or gets a rude awakening while 25 feet up in a bucket.
Randy

[DryCamper11]

Kiwi_too wrote:
I have not read all of the above but let me tell you how we did it.

In essence, you constructed a permanently installed 120 VAC extension cord that ran from near your RV to the only item you needed to power - your furnace - and you connect the generator in your RV with a temporary extension cord to the permanent extension cord. That works for you since you have mostly gas appliances and the cost of $200 was quite reasonable.

For comparison, I spent about the same amount for a 120/240 socket, wiring, new breaker and an interlock kit that lets me power any of the circuits in my home, including my 240 VAC well pump. Nothing needs to be disconnected or unplugged when I switch to the generator, and no modifications to a furnace or any other devices are needed.

I don't have any gas appliances - except in the RV. 🙂

[AllegroD]

I have not read all of the above but let me tell you how we did it.

First, we have a gas stove/range/oven, gas WH and a gas furnace, with heat pump. We added THIS INLET to the outside of the attached garage, beside where the MH sits. Inside the inlet ran to a dual 120/20 amp socket. We added the same setup from garage to inside the back door. We labelled both inside dual sockets "RV Inlet".

This allowed us to run one standard 20 amp (10 gauge) power cord from MH outside to garage, and did not setup a dead man's cord. We had the furnace wired by a professional to ensure no electrical problems do the furnace normally plugged into a 120/15 amp (remember it is gas and only has to run the thermostat and blower). This allowed us to run 2 extension cords from the MH to garage inside socket. One to the furnace and one to the garage to house socket. We only use the one going into the house for very small items, mostly lighting on the first floor. We have a number of battery operated laterns.

This allows us to heat the house, cook and shower.

Cost of the above was than $75 for the 4 electrical receptacles and a couple of electrical cords. The rest, 10g wire, elec cords, we already had. The furnace wiring cost $125.

[DryCamper11]

beemerphile1 wrote:
If you want to rely on your generator as backup power don't forget fuel. In a power outage or disaster fuel may not be available.

I keep my RV filled - 100 gallons - it should last through most power outages of less than a week. I don't run 24/7. Those who do this seriously (plan alternate power systems) recommend natural gas as the best option, but you may need to upgrade the NG supply system. Propane is second best, as it has indefinite lifetime in storage. A multifuel generator makes sense.

[beemerphile1]

I have enough 10 gauge cord to run from the RV to the house. I take the power straight from the 3,600 watt Onan.

When it gets to the house, I have a home made splitter into two 15 amp circuits. I used a J-box, two 15 breakers, and two 15/20 amp duplex.

I did a little mod to my home forced air furnace. It was initially hardwired but I changed it to a plugin. Now I can unplug from house power and plug into generator power.

I run cords to the refrigerator and two freezers as needed. None of them need to be powered 24/7. I can also run a cord to the entertainment center or other loads as desired.

Of course I also have 3 portable generators to be used as needed.

If you want to rely on your generator as backup power don't forget fuel. In a power outage or disaster fuel may not be available. I keep two 15 gallon drums of gasoline in the garage treated with Stabil and replenished once per year at least.

[DryCamper11]

mlts22 wrote:
There are a few ways to skin this cat and be up to code standards:

1: A circuit breaker interlock. This puts the incoming generator at the top right breaker, a device that only allows the main switch or the generator switch to be on, never both, and the top right breaker goes to a -male- connector on the outside. No widow maker cable needed, ever.

2: A sub-panel as mentioned above.

3: A manual transfer switch.

4: An automatic transfer switch. This is the easiest because one can just fire up the generator, let it warm up, plug it in, and the ATS takes over from there. When power comes back on, the ATS swaps back to mains lines.

I like the sub-panel or transfer switches because it is a lot more idiot-resistant than the interlock (as the interlock can fall off), but all of these are generally approved by electrical code in all areas.

Of course, one can run extension cords from the generator inside the house as well.

Backfeeding isn't a good idea. Those step-down transformers by the house? They will step up the voltage down the power lines when backfed.

This post by mlts lists all the options. I'll add some comments about cost. Option 4 (the ATS) is the most expensive, but it's also the most automatic. Personally, I don't mind turning some switches to save that expense. An ATS may have some maintenance requirements that manual switches avoid.

Option 3 is a transfer switch located between your home and the incoming power from the power lines. You throw the transfer switch and your home is disconnected from those power lines and connected to the gen. This is the safest for power company workers. It's expensive to install for two reasons. The first is that the TS needs to be rated for your home power. If you have a 200A service, then that 200A is passing through the new TS at your service entrance. High power, service entrance rated is expensive and you need that high power rating, even if you are only installing a 16A generator. The second cost comes from the fact that to install it at the service entrance, you need to have the power company turn off your power during installation. Your electrician can't do this alone. These costs also apply to option 4.

Option 2 is the most widely used. Basically, it's a simple sub panel. You move the breakers for a selected set of circuits hyou want to use during a power outage into that new subpanel, or you buy new ones. You need space to install the new subpanel. You need to move the wires that currently go to from your main panel to the various rooms in your house from your main panel into the new subpanel. Some may not be long enough, and they may need to be extended. The good news is that your electrician can do all this work without calling the power company. You are limited to powering only the circuits you select. If you decide you don't need to power the garage, or run the fan in the guest bathroom, then during the outage, you need lights in the garage, or want that fan, you are out of luck.

Then there is option 1. It is by far the cheapest. Electrically, it is nearly identical to the "suicide cord" and "dryer plug backfeed" that is universally illegal, except it is approved by the National Electrical Code (NEC and most local codes. The differences are subtle, but critical for safety. First, it requires an interlock so the main breaker (connecting your home to the power company)) can never be on when the generator breaker is on and vice-a-versa. Second, it needs a new breaker for the generator instead of using the dryer breaker. Often, that new breaker will be identical to your dryer breaker. Third it requires a new generator connection point socket (with male pins) instead of using the dryer receptacle so that your generator doesn't use a suicide cord. It uses a normal extension cord having a female end, so you don't have exposed pins when the gen is on. All of the options above need this new generator socket.

If the new generator socket was replaced with a dryer receptacle, and the interlock was removed, you'd have a normal dryer receptacle (or a second one, if you already had one.) Electrically, this type of installation is otherwise identical to backfeeding through the dryer plug, but it's done safely and according to the applicable electrical codes.

People are often surprised that it is legal to "backfeed" through a normal dryer circuit breaker when an interlock is installed, but this practice has been legal for many decades, and has often been used in industry. Almost all circuit breakers are rated for backfeeding. They must be specially marked if they are not, and all those sold by Home Depot that I've seen can be used in this type of legal backfeeding installation as long as a legal interlock is also used.

The cost advantages of option 1 are multiple, which is why I went with that option. I had no space for the new subpanel. My circuits wouldn't reach to where it would have to be installed, so I would have needed to extend all of them.. Plus, I wanted to be able to power everything in my home - not all at once - but I wanted to be able to turn on any circuit breaker and know I could send power out that circuit.

edit: I didn't list it, but one other subtle difference is that the generator breaker needs to be held down with additional clamps. Their cost is minor and they are often included with the interlock kit.

[FSAD]

Listen, I'm going to just use my big outlet in the elect cord compartment and run off that with a cord to the house, like I said in my last post, and thanks to Bobbo's reminder.

Thanks for all the input, wow, I can't believe how many replies I got in such a short time. thanks again.

mikey

[ksg5000]

Our concern was powering our house gas furnace when we get an ice storm which can take down the power lines - my electrician neighbor hooked up a pigtail on the furnace along with a DPDT switch (to prevent back feeding power lines) allowing me to run an extension cord from the RV. Don't use often but cheap insurance.