[GMCnet] ONAN wiring

[Randy]

I know you electrical wizards got this down cold, but me and AC power have never gotten along too well.

Onan Emerald 3 6500 gasoline

Coach has Red, Black, White, Green wires (1 each). Genset has 2 Black, 2 White and Green. Green is no problem. I want 120V from the genset. I would
imagine 2 Whites join the coach White, but what about Red and Black? I don't need the 240V capability. Any advice?
--
Randy
1973 26' Painted Desert
Ahwatukee (Phoenix) AZ


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[Matt Colie]

Luvn737s wrote on Sun, 08 February 2015 16:57

> I know you electrical wizards got this down cold, but me and AC power have never gotten along too well.
>
> Onan Emerald 3 6500 gasoline
>
> Coach has Red, Black, White, Green wires (1 each). Genset has 2 Black, 2 White and Green. Green is no problem. I want 120V from the genset. I
> would imagine 2 Whites join the coach White, but what about Red and Black? I don't need the 240V capability. Any advice?

Randy,

There is a problem. Not insurmountable, but real none the less.
Your color set would say it is set up for 240.
Emerald IIIs came as both 120 and 240V output. Most, I was told, were convertible. The only online manual I can find
http://hmcmotorhomes.homestead.com/files/2011_Manuals/Onan_Generator/Service-Manual/Onan_Serv_Manual_Pg_33-40_web.pdf
does not identify colors, but as numbers. If there are M-numbers on the leads, you are set.

You could start it and measure the voltage between leads and figure it out......

If your coach is a GMC fit interior, you could use it as 240.

Matt
--
Matt & Mary Colie - Members GMCMI, GMCES
'73 Glacier 23 - Still Loving OE Rear Drum Brake with Applied Control Arms
SE Michigan - Twixt A2 and Detroit

[Ken Burton]

Hook the two greens together.

Hook the three whites together.

Hook one black from the generator to the black in the coach

Hook the other black from the generator to the red in the coach.

You are done.

You do not care if the generator is 120 or 240 VAC the above wiring will work for both.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

[Randy]

Thanks. What keeps 240V from coming out of the outlets in this configuration?

[Ken Burton]

Oh boy, I'll try to explain this.

If it is a 240 volt generator, between the the two black wires on the generator there is 240 volts. Between either black wire and the white wire it
is 120 volts. In your coach distribution panel (circuit breaker box), there is nothing hooked between the two black (or black and red) wires. So
nothing in the coach will see 240 volts. Everything in the coach is hooked between a black or red wire and a white wire which is always 120 volts.

This the same thing that happens when you plug into 240 volt shore power.

--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

[Robert Mueller]

Yo Ken,

Remember the old adage "one picture is worth a thousand words?" Well here's hundreds of pictures! :-)

Tiny URL: http://tinyurl.com/k43uhtf

Full URL:

https://www.google.com.au/search?q=120+vac+wiring+vs+240+vac+wiring&espv=2&biw=1024&bih=681&tbm=isch&tbo=u&source=univ&sa=X&ei=wrPYV
LbsLouA8gX8rYJI&ved=0CCgQsAQ

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426

-----Original Message-----
From: Ken Burton

Oh boy, I'll try to explain this.

If it is a 240 volt generator, between the the two black wires on the generator there is 240 volts. Between either black wire and
the white wire it is 120 volts. In your coach distribution panel (circuit breaker box), there is nothing hooked between the two
black (or black and red) wires. So nothing in the coach will see 240 volts. Everything in the coach is hooked between a black or
red wire and a white wire which is always 120 volts.

This the same thing that happens when you plug into 240 volt shore power.
--
Ken

[Randy]

Thanks guys that does make sense.

[Randy]

SHE'S ALIVE!!!

A great big thanks to Ken, Matt, Mike and Mark here in AZ and Rob down-under for their guidance. I had my doubts when my Craigslist Onan showed up
just before Christmas, but it runs smoothly and quietly and carries the load. AC output is between 115-123 VAC and the governor seems to do a good job
of keeping it steady.

[Chris Tyler]

"red wire and a white wire which is always 120 volts.

This the same thing that happens when you plug into 240 volt shore power. "
--
Ken

Do you still have a ground with a 3 prong [30 amp] plug on 240v? Or does it matter?
Should it be a 4 wire [50 amp?}

I have thought about putting a 240 outlet out at my well service box for welding in the driveway. It would also be a handy place to plug the GMC in as
well on occasion if this can be done


--
76 Glenbrook

[D C _Mac_ Macdonald]

I had a 250V / 50A and a 125V / 30A outlet (in weatherproof boxes) installed on the side of my garage.

With a manual changeover switch, I can switch them between commercial power or my 8 kW generator.

Works great to power either the GMC with split 250V or my 30 foot travel trailer with 125V.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
~~ ~ D C "Mac" Macdonald ~ ~~
~ ~ Amateur Radio - K2GKK ~ ~
~ ~ USAF and FAA, Retired ~ ~
~ ~ ~ Oklahoma City, OK ~ ~ ~
~~ ~ ~ "The Money Pit" ~ ~ ~~
~ ~ ~ ~ TZE166V101966 ~ ~ ~ ~
~ ~ ~ '76 ex-Palm Beach ~ ~ ~
~~ k2gkk + hotmail dot com ~~
~ www.gmcmhphotos.com/okclb ~
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
______________
*[ ]~~~[][ ][|\
*--OO--[]---O-

> Date: Mon, 9 Feb 2015 15:01:51 -0700
> To: gmc...@temp.gmcnet.org
> From: dtyl...@tampabay.rr.com
> Subject: Re: [GMCnet] ONAN wiring

[Ken Burton]

Chris Tyler wrote on Mon, 09 February 2015 16:01

> "red wire and a white wire which is always 120 volts.
>
> This the same thing that happens when you plug into 240 volt shore power. "
> --
> Ken
>
> Do you still have a ground with a 3 prong [30 amp] plug on 240v? Or does it matter?
> Should it be a 4 wire [50 amp?}
>
> I have thought about putting a 240 outlet out at my well service box for welding in the driveway. It would also be a handy place to plug the GMC
> in as well on occasion if this can be done

I'm not sure I understand your question and what you want to do.

That said if you have a 240 volts appearance at that well and want to use it for something else I see a problem. How will you turn it off and on?
Currently there is a well pressure switch doing that and you will only be able to weld when the pressure switch calls for the well to run. Most wells
do not draw much current so the wire used is probably too thin to support a welder.
The Welder will have to be 220 because there is not normally a white neutral wire run to a well.

--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

[Chris Tyler]

My question is if I were to install an outlet at the junction box, could I plug in the GMC without a problem.
A 3 wire plug would be 2 hots and a neutral, right? So, is not having a ground an issue for the GMC?
If I run a 4 prong plug, that would be 2 hots, a neutral and ground?

I have 40 amp service to the well. I recently had a new submersible one put in. The old one had pretty heavy wire . Not sure about the new one, but
its raining and cant look at it right now.
On the new installation there is a junction box with a disconnect ahead of the pressure switch. It would not be that hard to put an outlet in, in a
weatherproof box.

Im not an electrician [obviously] and would be geting some qualified help if I do this. Im asking in terms of general feasability.

You are probably right regarding an arc welder, at least on the higher settings...although I run that on the dryer outlet with an heavy gauge
extention cord currently without problems.
My MIG runs much better on the hgher voltage. I also have a TIG which Im just learning on, but doesnt pull that many amps.
--
76 Glenbrook

[Ken Henderson]

Chris,

A couple of things that need to be emphasized (I now see reiterating KenB's
comments):

1. The 30A plug is strictly for 120 vac -- NO 240 vac. It does use
neutral and ground wires.

2. If your well is wired like mine, only 240 vac is available there -- NOT
120 vac. That is, there is no neutral wire to "center" the 240 to 120 vac
"split". Also, my pressure switch is inside the house on the storage tank,
so there's usually no power at the well. Even if your pressure switch is
at the well so you can connect before it, the wire probably won't support
much current.

Ken H.

On Tue, Feb 10, 2015 at 5:01 AM, Ken Burton <n9...@comcast.net> wrote:

> Chris Tyler wrote on Mon, 09 February 2015 16:01
> > "red wire and a white wire which is always 120 volts.
> >
> > This the same thing that happens when you plug into 240 volt shore
> power. "
> > --
> > Ken
> >
> > Do you still have a ground with a 3 prong [30 amp] plug on 240v? Or does
> it matter?
> > Should it be a 4 wire [50 amp?}
> >
> > I have thought about putting a 240 outlet out at my well service box for
> welding in the driveway. It would also be a handy place to plug the GMC
> > in as well on occasion if this can be done
>
>

[D C _Mac_ Macdonald]

IF your coach has the big 50A cable plug and socket combination, and nobody has screwed with the stock configuration, there should be NO PROBLEM using a STANDARD 50A 240V shore power connection.

As has been stated, a "normal" well 240V power is NOT a "split" (120-0-120) supply and is NOT compatible with the power input for the GMC.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
~~ ~ D C "Mac" Macdonald ~ ~~
~ ~ Amateur Radio - K2GKK ~ ~
~ ~ USAF and FAA, Retired ~ ~
~ ~ ~ Oklahoma City, OK ~ ~ ~
~~ ~ ~ "The Money Pit" ~ ~ ~~
~ ~ ~ ~ TZE166V101966 ~ ~ ~ ~
~ ~ ~ '76 ex-Palm Beach ~ ~ ~
~~ k2gkk + hotmail dot com ~~
~ www.gmcmhphotos.com/okclb ~
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
______________

|[ ]~~~[][ ][]\
"--OO--[]---O-"


> Date: Tue, 10 Feb 2015 06:43:25 -0700

> To: gmc...@temp.gmcnet.org
> From: dtyl...@tampabay.rr.com
> Subject: Re: [GMCnet] ONAN wiring
>

[Matt Colie]

Chris Tyler wrote on Tue, 10 February 2015 08:43

> My question is if I were to install an outlet at the junction box, could I plug in the GMC without a problem.
> A 3 wire plug would be 2 hots and a neutral, right? So, is not having a ground an issue for the GMC?
> If I run a 4 prong plug, that would be 2 hots, a neutral and ground?

> <Snip>

Chris,

To answer your first question as posted and shown above:
Yes, not having a ground in the receptacle would be dangerous.
The coach has no safety ground and without that getting passed along through the cable, there is the distinct potential for the coach chassis to
become other than ground and that could be really bad and even deadly.

Answer to your second question:
If you can create a local ground for this box (like tying to a metal well casing), that could work.
Then you put a 14-50 in the box and you are both safe and done.

Matt
--
Matt & Mary Colie - Members GMCMI, GMCES
'73 Glacier 23 - Still Loving OE Rear Drum Brake with Applied Control Arms
SE Michigan - Twixt A2 and Detroit