Onan Generator as emergency backup

tyler

Active member
Jun 22, 2013
518
98
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I would like the 6K Onan to power my actual house (not the coach "house" side, that already is fine as engineered) in case of hurricane, ice, etc.

As I look at common ways to hook up a standalone generator to house, simplest seems to be self contained generator with four prong plug, wire, and
double pole double throw interlock kit. Then you have two hots (bonafide 240 possible), white and green all separate to hook up to similar in main
panel.

Here is my question/confusion (terminology as well as concept) - As I understand it, the Onan ground is bonded at the generator, and my house (neutral
and ground) is bonded at the main breaker panel box. So, can I hook the four plug 50 of the coach to the four expected connections in my house panel?
I understand I will lose any 240 applications because of the Onan while serving both legs with 120. Goal is functional, safe and legal.
--
1975 Glenbrook, 1978 Royale rear bath
Raleigh, NC
 
Entirely for what its worth. I had an electrician install a manual transfer switch that is hooked up to the house furnace, and is powered by a plug
with a male end on it. This is for winter emergencies so I can run the Onan with an extension cord into that transfer switch. This keeps the house
warm and the blower motor on the furnace does not draw that much juice. There is enough power to also run a few plugs into the fridge, a basement
deep freezer if needed and a few lights.

Same for summer but I don't run the A/C that much to begin with and not when there is a power outage, The Onan's got plenty of power and I have
enough extension cords to run the fridge and a few lights. If we need to cool down I can run one of the Roof A/Cs in the coach and everyone's happy
"camping" in the driveway.

Total cost was about 50 bucks. Depending on whether you "need" A/C in the summer, or just need to keep the fridge on I suppose is the difference.
No modifications needed to the coach. For us, having heat in the winter is a must to keep things from freezing and bursting in sub 0 weather. The
house hot water tank is Gas as is the stove, so it makes no difference if there is power or not Just have to light the burners with a match.

Bonus I suppose is the Onan is not that loud and it has 40+ gallons of gas to feed it. So Im not out there filling up a smaller generator every few
hours.
--
77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy.
Mid Michigan
 
So if you turn the main barker off and all the 220-volt branch circuits
then add a pair of 30 amp breakers to be back-fed from a 50 amp cable
plugged into your coach would be a starting point. You would then need to
shed as much load as possible before you start your generator. This does
not meet code if there is a way to have the main breaker and your
back-feed breaker on at the same time. It would not hurt to monitor your
current with a clamp-on meter as you add load.

> I would like the 6K Onan to power my actual house (not the coach "house"
> side, that already is fine as engineered) in case of hurricane, ice, etc.
>
> As I look at common ways to hook up a standalone generator to house,
> simplest seems to be self contained generator with four prong plug, wire,
> and
> double pole double throw interlock kit. Then you have two hots (bonafide
> 240 possible), white and green all separate to hook up to similar in main
> panel.
>
> Here is my question/confusion (terminology as well as concept) - As I
> understand it, the Onan ground is bonded at the generator, and my house
> (neutral
> and ground) is bonded at the main breaker panel box. So, can I hook the
> four plug 50 of the coach to the four expected connections in my house
> panel?
> I understand I will lose any 240 applications because of the Onan while
> serving both legs with 120. Goal is functional, safe and legal.
> --
> 1975 Glenbrook, 1978 Royale rear bath
> Raleigh, NC
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

--

*John Phillips*
 
Best to have a licenced Electrician hook this up for you so it is done right the first time!

Have him wire the required circuits (furnace, fridge, freezer, well pump etc) into a separate breaker subpanel. Then using a proper transfer switch,
wire the small sub panel through the transfer switch to the main panel. The generator is wired with a 50 Amp cable into the transfer switch's
generator input.

When the power fails, the transfer switch will disconnect from the mains and switch to the generator input. Start your generator and plug in the cable
from the transfer switch. The generator will now power the equipment connected to the sub panel. When the main power returns and is stable for a set
period of time, the transfer switch will switch the subpanel back to main power. This will leave your generator running but the load has been removed,
so you need to manually shut down the generator.

This is how we provide backup generator for radio communications towers for Fire Departments. Most are Volunteer Departments with no cash for
automatic generator systems. The equipment is backed-up with batteries as well, but for a prolonged outage they can take a portable generator to the
tower site. They just start it and plug it in. It automatically transfers back to main power when it is restored.

Just remember only 120V equipment can be powered by the Onan. My well pump is 240V so I have a 12Kw generator for my Kubota tractor.
--
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
 
I was looking at that as well, but opted for the portable generator route. Coach is parked out front (I would need at least 100' cable - $$$$, or an
electrician to feed the circuit under the house and up to the panel - also $$$), under cover and I considered having to re-winterize (in the winter!)
if I did have to run it for a winter power outage.

I am NOT an electrician, by ANY stretch of the imagination. Up in Canada the interlock kit is not legal, so I installed a Reliance 10-circuit manual
transfer switch (myself - it wasn't rocket science thank God - excellent instructions). I already had 2 Honda eu2000 generators (one of them the
Companion so I have a L5-30P receptacle) and the parallel cables. Converted them both to propane (again an easy mod - Thanks Hutch Mountain!)

I have tested the set-up for several hours, & I can run my furnace, heat tape in the crawl space, a number essential lights, office, TV, fridge,
microwave, toaster oven, coffee machine (can't run those last 3 at the same time - too much wattage, but I never do that anyway!) And this is in Eco
mode. Plenty to get me by for several days if need be. Don't need the oven (convection toaster oven is all I use now anyway), laundry is not high on
the list of priorities during a power outage, and if I need hot water I can heat it up in the microwave (water heater should stay reasonably hot for
quite some time anyway - well insulated!) Not counting the Hondas (already had those) my total expenditure was $1500 (CDN) and took about 2 days
total. And I don't have to worry about filling them up with gas every few hours. I can run a good 12-18 hours (or more) on a 20 lb tank of propane
and I can store it indefinitely. I plan to have 2 tanks on the deck.

As much as I would have loved to use the Onan (6K vs 3.2K), it just wasn't as workable for me. And to be honest - I think I can count on my Hondas
for a very long period of time. I need to know that I can pull the cord and they will start. The Onan, as good as she is right now (and she is
good!), is not something I would want to stake my pipes on in the sub-zero temps up here. Crawl space gets pretty cold without some heat and the
plumbing would burst.

--
Deb McWade
Logan Lake, BC, CAN
"Li'l Sister"
'77 Kingsley, 403, EBL EFI;
TZE167V101404
It's Bigger on the Inside!
 
For reliability, I'll take the Onan over pretty much anything. It's simple and an anvil. Since I use natural gas for cooking, heating, and clothes
dryer, the 6KW runs everything but the A/c - furnace because it's 220V. I have a 35K BTU gas heater in the largest room and it keeps the entire
house warm enough to bear. We seldom see even the 20s here.
There are several ways to set it up into the house. Bruce's setup is the premium. I don't think in your home a load shed panel is necessary. Simply
mark the breakers to turn off and you're good to go. We put load shed panels where the site, like many of his, is unattended and there's nobody to
turn the breakers off. The salient point however is the two position wall switch, which should have a visible air gap between sources.. the UP
commercial, middle off, down genset is the common one. Around here it must be accessible by power company techs... put it beside the power meter.
Second best, also legal and safe, is some extension cords for the essentials - icebox, freezer, lights. Blower in a gas heater. Third best works but
>IS NOT LEGAL, AND CAN BE DANGEROUS
 
Even if you turn off non-essential circuits you still need to be careful
not to overload the generator. 6KW is great for the GMC but a house can be
a lot more load than that.

On Fri, Jan 25, 2019 at 3:04 PM Johnny Bridges via Gmclist <

> For reliability, I'll take the Onan over pretty much anything. It's
> simple and an anvil. Since I use natural gas for cooking, heating, and
> clothes
> dryer, the 6KW runs everything but the A/c - furnace because it's 220V. I
> have a 35K BTU gas heater in the largest room and it keeps the entire
> house warm enough to bear. We seldom see even the 20s here.
> There are several ways to set it up into the house. Bruce's setup is the
> premium. I don't think in your home a load shed panel is necessary. Simply
> mark the breakers to turn off and you're good to go. We put load shed
> panels where the site, like many of his, is unattended and there's nobody to
> turn the breakers off. The salient point however is the two position wall
> switch, which should have a visible air gap between sources.. the UP
> commercial, middle off, down genset is the common one. Around here it
> must be accessible by power company techs... put it beside the power meter.
> Second best, also legal and safe, is some extension cords for the
> essentials - icebox, freezer, lights. Blower in a gas heater. Third best
> works but
> >IS NOT LEGAL, AND CAN BE DANGEROUS the genset connects, turn off the master breaker, turn the genset and its
> breaker on. The problem with the last is, if you forget to turn the
> master breaker off, you're backfeeding the power line. Usually this simply
> stalls the genset or takes its breaker out because the load is many times
> its capacity. The fear is, if the break is close and being worked on, you
> can electrocute the worker.
>
> --johnny
> --
> Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
> Braselton, Ga.
> "I forgive them all, save those who hurt the dogs. They must answer to me
> in hell" - ol Andy, paraphrased
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

--

*John Phillips*
 
And what Johnny said in his last sentence actually and unfortunately happens many times a year in the USA!

D C "Mac" Macdonald​
Amateur Radio K2GKK​
Since 30 November '53​
USAF and FAA, Retired​
Member GMCMI & Classics​
Oklahoma City, OK​
"The Money Pit"​
TZE166V101966​
'76 ex-Palm Beach​
k2gkk + hotmail dot com​

________________________________
From: Gmclist on behalf of Johnny Bridges via Gmclist
Sent: Friday, January 25, 2019 16:51
To: gmclist
Cc: Johnny Bridges
Subject: Re: [GMCnet] Onan Generator as emergency backup

For reliability, I'll take the Onan over pretty much anything. It's simple and an anvil. Since I use natural gas for cooking, heating, and clothes
dryer, the 6KW runs everything but the A/c - furnace because it's 220V. I have a 35K BTU gas heater in the largest room and it keeps the entire
house warm enough to bear. We seldom see even the 20s here.
There are several ways to set it up into the house. Bruce's setup is the premium. I don't think in your home a load shed panel is necessary. Simply
mark the breakers to turn off and you're good to go. We put load shed panels where the site, like many of his, is unattended and there's nobody to
turn the breakers off. The salient point however is the two position wall switch, which should have a visible air gap between sources.. the UP
commercial, middle off, down genset is the common one. Around here it must be accessible by power company techs... put it beside the power meter.
Second best, also legal and safe, is some extension cords for the essentials - icebox, freezer, lights. Blower in a gas heater. Third best works but
>IS NOT LEGAL, AND CAN BE DANGEROUS
 
Based on actual experience during Hurricane Katrina, from close to ground zero.
I ran extensions cords from Mr. Onan into my house and plugged in the frig only. Also, ran extension cord to my neighbor's house for the same
purpose.
While others were running around (unprepared) like chickens with their heads cut off, I enjoyed the comfort of the GMC with A/C, frig, hot water and
color tv. Just my method of attacking power loss.
If I really thought the threat was massive, I would point the coach away from the area.
We were without power for 11 hours. Not a long time, but with full gas tanks, I felt safe. With hurricanes, the current advice is prepare for three
days loss of power and public water supplies. My approach is seven days. MRE's are your friend.
Tom
--
2012 Phoenix Cruiser model 2552
KA4CSG
 
Thanks for all the replies, usage and experience are awesome.

I found
http://noshockzone.org/category/rv-safety/
to have a helpful array of RV articles about electricity.

Sort of to answer my own question about the neutral/ground bond (if future readers have similar question), I found the following internet answer to be
the most complete and logic oriented. It basically says since the generator is AT the fuse panel, the double path is not an issue.

In a normal circuit yes it would be a problem to have a bonded neutral and ground, but in a temporary generator feed it is much less of a concern. It
is more of a theoretical issue, but given that your generator cord is going to have an insulated ground conductor, even that is somewhat implausible.
You will have created a parallel neutral feed, but since we're talking a main panel neutral and ground really are the same thing at that point. The
generator being bonded is sort of like the service entrance mast or meter socket box in that the neutral and ground are bonded at multiple points
through them. The neutral is technically an insulated conductor running through the mast, but it's sometimes bonded at the top of the mast where the
ACSR drop lashes, bonded in the meter can to the metal box, sometimes bonded via a bonding bushing, and bonded again in the main panel; the steel
framework is electrically indistinguishable from the neutral conductor itself. Adding the generator frame to what bonding already exists in the
service entrance really is not a big leap.
From
https://www.doityourself.com/forum/electrical-ac-dc/555838-connecting-portable-generator-bonded-neutral-house-panel.html


--
1975 Glenbrook, 1978 Royale rear bath
Raleigh, NC
 
Just wire it up as you describe and you will be fine. All of the equipment manufacturers wire their generators the same as that is the way the NEC says the equipment has to be designed. UL will verify that when they get a generator for evaluation.

As far as the bonding of the neutral and the ground wire on the main panel of your home. It is required that the neutral and the ground be bonded together in exactly ONE location per building.
If you connect the safety ground and the neutral in subpanels, that will cause a ground loop, which will not allow GFCI devices to work correctly.

As to generator capacity, your 6KW Onan should be fine. I have a 6500 watt Sears generator for a home with electric range, electric dryer, a well and pressure pump, with four residents. Just don't try to do multiple things at the same time. Our generator has provided us with energy as long as 14 days. Needless to say, you only run it intermittently as your supply of fuel is your limiting factor. Finding and being able to buy fuel is going to be a challenge as gas stations are not required to have standby power, at least where we live.

>
>
> I would like the 6K Onan to power my actual house (not the coach "house" side, that already is fine as engineered) in case of hurricane, ice, etc.
>
> As I look at common ways to hook up a standalone generator to house, simplest seems to be self contained generator with four prong plug, wire, and
> double pole double throw interlock kit. Then you have two hots (bonafide 240 possible), white and green all separate to hook up to similar in main
> panel.
>
> Here is my question/confusion (terminology as well as concept) - As I understand it, the Onan ground is bonded at the generator, and my house (neutral
> and ground) is bonded at the main breaker panel box. So, can I hook the four plug 50 of the coach to the four expected connections in my house panel?
> I understand I will lose any 240 applications because of the Onan while serving both legs with 120. Goal is functional, safe and legal.
> --
> 1975 Glenbrook, 1978 Royale rear bath
> Raleigh, NC
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org