For Those Going Solar and Removing Onan...

M

mark sawyer

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Has anyone considered or is currently running one of those belt-driven 120v generators? Looks like these are common on some modern coaches that are
going genset-less... They also seem to be used on emergency equipment, and also to some extent on boats.

Was looking for opinions, and if anyone has first hand experience with how well they work, cost, etc... Not sure I'd want to rip out my Onan and
install one of these... But if you had a primarily solar coach, I think this would be a nice to have backup if you ran in to a string of cloudy days,
unexpected situations, etc.

This company seems to make a fairly popular unit. Looks like they offer 110 and 220v units in the 2-3k watt range. They also seem to offer a voltage
regulator to keep the gen's output constant as engine rpms change:

http://www.fabcopower.com/generat/bgen.htm
--
Mark S. '73 Painted Desert,
Manny 1 Ton Front End,
Howell Injection,
Leigh Harrison 4bag and Rear Brakes,
Fort Worth, TX
 
Several years ago, we bought some %kw units from an outfit that supplied them to the maker of the Navy's riverine boats. Custom mounts for whatever
you specified, automatic throttle control for the engine, and a sine wave inverter for the output. In a 350 Econoline, you never ran the engine over
1900 RPM to make 5 KW.

--johnny
--
'76 23' transmode Norris upfit, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"The road goes on forever, and the party never ends" --Robert Earl Keen
 
> Has anyone considered or is currently running one of those belt-driven 120v generators? Looks like these are common on some modern coaches that
> are going genset-less... They also seem to be used on emergency equipment, and also to some extent on boats.
>
> Was looking for opinions...
You already have an alternator on the engine that will run the house 12vdc stuff AND charge the house battery via the converter/charger through the
isolator. You will probably already have an inverter for the 120vac stuff.

You won't gain anything by adding another engine driven generator. A different one won't charge the battery bank any faster than the converter/charger
you have, whether it is running on shore power or off the engine alternator through the isolator.

I guess I am saying if you decide to remove the Onan and use something on the Olds engine to replace it, you won't gain anything by adding another
belt driven device to the Olds engine. You already got what you need.
--
73 23' Sequoia 4 Sale
73 23' CanyonLands Parts Unit 4 Sale
Upper Alabama
"When I grow up I am going to be a curmudgeon."
 
I would not want to turn that whenever the engine was running, so unless you had some sort of Mad Max electric clutch that would kill it for me. I
would also worry about the frequency. I only read the ad lightly but the engine rpm would cause the cps to fluctuate while driving.
Bottom line... it needs to be disconnected until the emergency occurs.
--
1977 26 foot 403
 
Except the Delcotron has a capacity of about 1100 Watts compared to 5KW for running say a roof AC
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
> I guess I am saying if you decide to remove the Onan and use something on the Olds engine to replace it, you won't gain anything by adding another
> belt driven device to the Olds engine. You already got what you need.

Well, the alternator/inverter wont handle all your power needs... I have a 2500 watt inverter on my coach, but I still use my generator all the time.
Less than if I had no inverter, but if I need to run the AC and I'm not on shore power, the generator gets run. Also, I can run the microwave
through the inverter, but it pulls a ton of current.... If I'm warming up more than a cup of coffee or a sandwich, I generally start the gen as well.


Also, using the alternator to charge the batteries is very slow. Especially at lower rpm where the alternator puts out little current. I have 4 golf
cart batteries, plus the engine battery, which I would imagine is a similar battery setup to someone on solar. Alternator generally does a good job
at keeping them topped off... But if I draw down all the batts, I'll run the genset and charge them through the inverter. I can generally get them
back to 80ish percent in around an hour. If I had to do that through the alternator at low rpm, it would probably take days...
--
Mark S. '73 Painted Desert,
Manny 1 Ton Front End,
Howell Injection,
Leigh Harrison 4bag and Rear Brakes,
Fort Worth, TX
 
> I would not want to turn that whenever the engine was running, so unless you had some sort of Mad Max electric clutch that would kill it for me. I
> would also worry about the frequency. I only read the ad lightly but the engine rpm would cause the cps to fluctuate while driving.
> Bottom line... it needs to be disconnected until the emergency occurs.

Clutching it is an interesting idea... However, I wonder how much parasitic loss it would cause if not generating power for a load? I think it would
work the same way as your 12v alternator... When your car alternator is not generating current, parasitic loss is low... As for the CPS, it appears
to have an optional regulator that keeps the voltage, and I assume the cps at 60 with varying engine RPM.

--
Mark S. '73 Painted Desert,
Manny 1 Ton Front End,
Howell Injection,
Leigh Harrison 4bag and Rear Brakes,
Fort Worth, TX
 
If you really want to evaluate the possiblity of using a 120 vac alternator
of high capacity on the engine, take a look at the alternator section of a
portable generator, or even the Onan that's in the coach. That's
approximately the size an engine-driven equivalent would be -- there's
really no reasonable way to significantly reduce the size. My engine
doesn't leave enough room in its compartment to mount such a device,
especially if one adds the clutch I'd consider essential.

JMHO,

Ken H.

On Wed, Feb 8, 2017 at 10:28 AM, Mark Sawyer
wrote:

> Has anyone considered or is currently running one of those belt-driven
> 120v generators? Looks like these are common on some modern coaches that
> are
> going genset-less... They also seem to be used on emergency equipment,
> and also to some extent on boats.
>
> Was looking for opinions, and if anyone has first hand experience with how
> well they work, cost, etc... Not sure I'd want to rip out my Onan and
> install one of these... But if you had a primarily solar coach, I think
> this would be a nice to have backup if you ran in to a string of cloudy
> days,
> unexpected situations, etc.
>
> This company seems to make a fairly popular unit. Looks like they offer
> 110 and 220v units in the 2-3k watt range. They also seem to offer a
> voltage
> regulator to keep the gen's output constant as engine rpms change:
>
> http://www.fabcopower.com/generat/bgen.htm
> --
> Mark S. '73 Painted Desert,
> Manny 1 Ton Front End,
> Howell Injection,
> Leigh Harrison 4bag and Rear Brakes,
> Fort Worth, TX
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Frequency output in alternators is a product of RPM'S, and the design of
the stator. If you do not stay within the recommended frequency design of
whatever you have plugged in, bad juju sometimes happens and you let out
the smoke from within. Automotive engines are difficult to stabilize for
specific exact RPM'S without governors. If loads are constant, you can get
close, but with changing loads, RPM'S and frequency will vary.
Onan engines are quite stable in RPM'S due to their 10 ball governor
on the camshaft. They literally are quicker in response to changes in load,
than the humans operating them.
Jim Hupy
Salem, Or
78 GMC ROYALE 403

> > I would not want to turn that whenever the engine was running, so unless
> you had some sort of Mad Max electric clutch that would kill it for me. I
> > would also worry about the frequency. I only read the ad lightly but the
> engine rpm would cause the cps to fluctuate while driving.
> > Bottom line... it needs to be disconnected until the emergency occurs.
>
>
> Clutching it is an interesting idea... However, I wonder how much
> parasitic loss it would cause if not generating power for a load? I think
> it would
> work the same way as your 12v alternator... When your car alternator is
> not generating current, parasitic loss is low... As for the CPS, it appears
> to have an optional regulator that keeps the voltage, and I assume the cps
> at 60 with varying engine RPM.
>
>
>
> --
> Mark S. '73 Painted Desert,
> Manny 1 Ton Front End,
> Howell Injection,
> Leigh Harrison 4bag and Rear Brakes,
> Fort Worth, TX
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Rectify it and invert it to 60HZ 120V. Now the engine speed follows the load. The ones we tried worked fine. We just weren't crazy about running a
Ford V10 for four - six hours at a time and reverted to Onans in future trucks. There wasn't any dollar savings. They weren't as large as the Onan
alternators, but they weren't mice either. The inverters were pretty good sized. The servo throttle controls worked OK, the fly-by-wire one did
somewhat better. I suspect Rostra made both of them.

--johnny
--
'76 23' transmode Norris upfit, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"The road goes on forever, and the party never ends" --Robert Earl Keen
 
There exists out there a form of engine speed control for applications like
air compressors and alternators that are intended for use with lighting
applications that are not frequency sensitive. They work similar to cruise
controls, and are about as accurate. Rostra may in fact be a manufacturer
of some of them. My experience with them is with service trucks that tire
stores use for roadside tire repair, and line repair trucks that need
strong lighting for storm damaged power lines. Their accuracy is good
enough for that use but lacks the precision for audio and similar
equipment. Be careful what you buy. I burned up some expensive Fender
amplifier equipment by using non stabilized frequency controlled inverters.
Built a portable marching band power supply for electronic guitars. Learned
expensive lessons there.
Jim Hupy
Salem, Or
78 GMC ROYALE 403

On Feb 8, 2017 2:31 PM, "Johnny Bridges via Gmclist" <

> Rectify it and invert it to 60HZ 120V. Now the engine speed follows the
> load. The ones we tried worked fine. We just weren't crazy about running a
> Ford V10 for four - six hours at a time and reverted to Onans in future
> trucks. There wasn't any dollar savings. They weren't as large as the Onan
> alternators, but they weren't mice either. The inverters were pretty good
> sized. The servo throttle controls worked OK, the fly-by-wire one did
> somewhat better. I suspect Rostra made both of them.
>
> --johnny
> --
> '76 23' transmode Norris upfit, 76 26' Eleganza(?) with beaucoup mods and
> add - ons.
> Braselton, Ga.
> "The road goes on forever, and the party never ends" --Robert Earl Keen
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Those are the controls used with the engine alternators. Most audio equipment wants to see a fairly clean sine wave for power... even the stepped
square wave stuff gives them indigestion, as you've seen. Usually it isn't so much the frequency as the waveform which creates the grief.

--johnny
--
'76 23' transmode Norris upfit, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"The road goes on forever, and the party never ends" --Robert Earl Keen
 
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