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[GMCnet] Oddity [message #105752] Fri, 12 November 2010 05:46 Go to next message
Steven Ferguson is currently offline  Steven Ferguson   United States
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Registered: May 2006
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Maybe not to some of you, but this is certaintly an oddity to me. The coach
I recently advertised here for sale is at our Thanksgiving rally here in
Benson, AZ. The new owner asked me about a device installed in the coach
that makes AC our of DC. This is entirely separate from the TruCharge 40
that is installed in place of hte old buzz box. This gizmo winds up like an
electric motor, has it's own compartmet (fairly large), makes plenty of
noise and will blow the main fuse if used while plugged into shore power.
Sorry, no pics as I would have to remove a panel to get to this. I'm not
entirely sure but I believe it was installed by Cinnabar.


--
Steve Ferguson
Sierra Vista, AZ
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Re: [GMCnet] Oddity [message #105753 is a reply to message #105752] Fri, 12 November 2010 06:13 Go to previous messageGo to next message
hasbeen is currently offline  hasbeen   United States
Messages: 66
Registered: August 2005
Location: Cave Creek, AZ
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Member
Steve, I remember a product used on the Holiday Rambler line (and possibly others) in the mid 80's that was mounted behind the grille area on their higher line coaches. It was very similiar to a swimming pool motor in size and appearance and made 110 volts from 12 volts. Just wondering if this is what you have there.... Jim
Re: [GMCnet] Oddity [message #105755 is a reply to message #105753] Fri, 12 November 2010 07:26 Go to previous messageGo to next message
Keith V is currently offline  Keith V   United States
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Registered: March 2008
Location: Mounds View,MN
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Senior Member
hasbeen wrote on Fri, 12 November 2010 06:13

Steve, I remember a product used on the Holiday Rambler line (and possibly others) in the mid 80's that was mounted behind the grille area on their higher line coaches. It was very similiar to a swimming pool motor in size and appearance and made 110 volts from 12 volts. Just wondering if this is what you have there.... Jim



Sounds like a dynamo. Basically an electric motor powered generator. So it's like 15-20% efficient?


Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
Re: [GMCnet] Oddity [message #105756 is a reply to message #105753] Fri, 12 November 2010 07:32 Go to previous messageGo to next message
Hardie Johnson is currently offline  Hardie Johnson   United States
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Registered: January 2004
Location: Raleigh NC
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Senior Member
hasbeen wrote on Fri, 12 November 2010 07:13

Steve, I remember a product used on the Holiday Rambler line (and possibly others) in the mid 80's that was mounted behind the grille area on their higher line coaches. It was very similiar to a swimming pool motor in size and appearance and made 110 volts from 12 volts. Just wondering if this is what you have there.... Jim

I remember a similar gadget on our C-119s whch was a motor-generator running off the aircraft DC to generate 400Hz ac for the aircraft electronics. It was called an inverter, and was a mechanical solution to the AC/DC problem* before solid state inverters were developed. That is likely what you have there, generating 120 VAC. If it pops breakers when the land line is connected, something is wired wrong. It is also hella inefficient.
*"not that I have a problem with AC/DC"


Hardie Johnson "Crashj"
1973 26 foot Glacier, White Thing
Raleigh NC
Re: [GMCnet] Oddity [message #105757 is a reply to message #105752] Fri, 12 November 2010 07:37 Go to previous messageGo to next message
Marsh Wilkes is currently offline  Marsh Wilkes   United States
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Registered: January 2004
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Senior Member
Hi Steve,

Interesting! It's a motor generator set, more commonly used to convert
single phase power to 3 phase power. For example you need to run a 3 phase
milling machine in a home workshop.
A motor generator set can be built to do any power conversion and before
modern inverters were common there weren't many choices for converting 12 or
24 volt DC into 120AC.

Here is a link to information on motor generator sets.
http://www.electricpowergenerator.com/motor-generator-sets.html

P. S. That Cad Camino was still sitting there last time I was by that way.

Marsh Wilkes
Perry Fl


----- Original Message -----
From: "Steven Ferguson" <botiemad11@gmail.com>
To: <gmclist@temp.gmcnet.org>
Sent: Friday, November 12, 2010 6:46 AM
Subject: [GMCnet] Oddity


> Maybe not to some of you, but this is certaintly an oddity to me. The
> coach
> I recently advertised here for sale is at our Thanksgiving rally here in
> Benson, AZ. The new owner asked me about a device installed in the coach
> that makes AC our of DC. This is entirely separate from the TruCharge 40
> that is installed in place of hte old buzz box. This gizmo winds up like
> an
> electric motor, has it's own compartmet (fairly large), makes plenty of
> noise and will blow the main fuse if used while plugged into shore power.
> Sorry, no pics as I would have to remove a panel to get to this. I'm not
> entirely sure but I believe it was installed by Cinnabar.
>
>
> --
> Steve Ferguson
> Sierra Vista, AZ
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

_______________________________________________
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Re: [GMCnet] Oddity [message #105758 is a reply to message #105757] Fri, 12 November 2010 07:47 Go to previous messageGo to next message
Marsh Wilkes is currently offline  Marsh Wilkes   United States
Messages: 155
Registered: January 2004
Karma: -3
Senior Member
This may be a better link


http://en.wikipedia.org/wiki/Motor-generator

Marsh Wilkes
Perry Fl

----- Original Message -----
From: "Marsh Wilkes" <gmc455@comcast.net>
To: <gmclist@temp.gmcnet.org>
Sent: Friday, November 12, 2010 8:37 AM
Subject: Re: [GMCnet] Oddity


> Hi Steve,
>
> Interesting! It's a motor generator set, more commonly used to convert
> single phase power to 3 phase power. For example you need to run a 3 phase
> milling machine in a home workshop.
> A motor generator set can be built to do any power conversion and before
> modern inverters were common there weren't many choices for converting 12
> or
> 24 volt DC into 120AC.
>
> Here is a link to information on motor generator sets.
> http://www.electricpowergenerator.com/motor-generator-sets.html
>
> P. S. That Cad Camino was still sitting there last time I was by that
> way.
>
> Marsh Wilkes
> Perry Fl
>
>
> ----- Original Message -----
> From: "Steven Ferguson" <botiemad11@gmail.com>
> To: <gmclist@temp.gmcnet.org>
> Sent: Friday, November 12, 2010 6:46 AM
> Subject: [GMCnet] Oddity
>
>
>> Maybe not to some of you, but this is certaintly an oddity to me. The
>> coach
>> I recently advertised here for sale is at our Thanksgiving rally here in
>> Benson, AZ. The new owner asked me about a device installed in the coach
>> that makes AC our of DC. This is entirely separate from the TruCharge 40
>> that is installed in place of hte old buzz box. This gizmo winds up like
>> an
>> electric motor, has it's own compartmet (fairly large), makes plenty of
>> noise and will blow the main fuse if used while plugged into shore power.
>> Sorry, no pics as I would have to remove a panel to get to this. I'm not
>> entirely sure but I believe it was installed by Cinnabar.
>>
>>
>> --
>> Steve Ferguson
>> Sierra Vista, AZ
>> _______________________________________________
>> GMCnet mailing list
>> List Information and Subscription Options:
>> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
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Re: [GMCnet] Oddity [message #105769 is a reply to message #105752] Fri, 12 November 2010 09:49 Go to previous messageGo to next message
Bob Horton is currently offline  Bob Horton   Canada
Messages: 81
Registered: December 2005
Location: Brandon, Manitoba, Canada
Karma: 0
Member
Sounds similar to the inverters we used to have in the old CF 100 fighters to convert 24 volt to 400 cycle AC for the radios and other electronics prior to the transistor age. Years later I came across similar devices (army surplus) used to convert from 12 or 24 volt to high voltages for army radios. When I was teaching electronics I used them to teach students how to use multimeters safely to read high voltages. It was scary but fun.

Bob Horton
Brandon, Manitoba
Re: [GMCnet] Oddity [message #105770 is a reply to message #105752] Fri, 12 November 2010 09:50 Go to previous messageGo to next message
GeorgeRud is currently offline  GeorgeRud   United States
Messages: 1380
Registered: February 2007
Location: Chicago, IL
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Senior Member
Though it is a bit of a relic, I love seeing these old electronics where engineers had to come up with basically mechanical solutions to electrical challanges.

I love the efficiencies of modern electronics, but it was neat to see the Wikipedia article.


George Rudawsky
Chicago, IL
75 Palm Beach
Re: [GMCnet] Oddity [message #105779 is a reply to message #105769] Fri, 12 November 2010 10:52 Go to previous messageGo to next message
k2gkk is currently offline  k2gkk   United States
Messages: 4452
Registered: November 2009
Karma: -8
Senior Member

Until the early 1960s and the development of transistors
stout enough to take 12 and 24 Volt DC, switch it back
and forth to make a square wave, feed it to a step-up
transformer, then rectify it to high voltage DC, mechanical
motor-generators(known as dynamotors) were virtually the
ONLY way to get the high voltage-high current power needed
for transmitters. It was also a reliable means to get lower
power for receivers.

The mechanical "vibrators" used in automobile radios were
simple, but generally short-lived devices to do the conversion
of 6V battery power to higher voltages needed in those radios.

The dynamotors have been around since the 1930s, at the latest.

After WW II, hams would take 12 and 24 Volt dynamotors and
rewire the windings to make them work on the 6 Volt cars of
the days. We learned to park our manual transmission cars
headed downhill so we could get a "gravity start" when we
used up so much battery power gabbing, that there wasn't
enough left to restart the car!


* * * * * * * * * * * *
* D C "Mac" Macdonald *
* Amateur Radio K2GKK *
* USAF & FAA, Retired *
** Oklahoma City, OK **
* * "The Money Pit" * *
* * ex-Palm Beach, 76 *
* * * * * * * * * * * *



* "An unarmed man can but flee *
* from evil. Evil can NEVER be *
* overcome by flight FROM it." *





> To: gmclist@temp.gmcnet.org
> From: bobsgmc@mts.net
> Date: Fri, 12 Nov 2010 09:49:46 -0600
> Subject: Re: [GMCnet] Oddity
>
>
>
> Sounds similar to the inverters we used to have in the old CF 100 fighters to convert 24 volt to 400 cycle AC for the radios and other electronics prior to the transistor age. Years later I came across similar devices (army surplus) used to convert from 12 or 24 volt to high voltages for army radios. When I was teaching electronics I used them to teach students how to use multimeters safely to read high voltages. It was scary but fun.
>
> Bob Horton
> Brandon, Manitoba
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
_______________________________________________
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Re: [GMCnet] Oddity [message #105781 is a reply to message #105779] Fri, 12 November 2010 11:02 Go to previous messageGo to next message
Harry is currently offline  Harry   Canada
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Registered: October 2007
Location: Victoria, BC CANADA
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Senior Member
We had "MG" sets to change AC to DC for smoother control on elevators.
They are now using rectifiers.
Re: [GMCnet] Oddity [message #105795 is a reply to message #105757] Fri, 12 November 2010 15:28 Go to previous messageGo to next message
Steven Ferguson is currently offline  Steven Ferguson   United States
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Registered: May 2006
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Senior Member
Thanks. I'd sure like to have one of those CadCaminos. I can't believe
it's still sitting there Marsh.

On Fri, Nov 12, 2010 at 5:37 AM, Marsh Wilkes <gmc455@comcast.net> wrote:

> Hi Steve,
>
> Interesting! It's a motor generator set, more commonly used to convert
> single phase power to 3 phase power. For example you need to run a 3 phase
> milling machine in a home workshop.
> A motor generator set can be built to do any power conversion and before
> modern inverters were common there weren't many choices for converting 12
> or
> 24 volt DC into 120AC.
>
> Here is a link to information on motor generator sets.
> http://www.electricpowergenerator.com/motor-generator-sets.html
>
> P. S. That Cad Camino was still sitting there last time I was by that way.
>
> Marsh Wilkes
> Perry Fl
>
>
> ----- Original Message -----
> From: "Steven Ferguson" <botiemad11@gmail.com>
> To: <gmclist@temp.gmcnet.org>
> Sent: Friday, November 12, 2010 6:46 AM
> Subject: [GMCnet] Oddity
>
>
> > Maybe not to some of you, but this is certaintly an oddity to me. The
> > coach
> > I recently advertised here for sale is at our Thanksgiving rally here in
> > Benson, AZ. The new owner asked me about a device installed in the coach
> > that makes AC our of DC. This is entirely separate from the TruCharge 40
> > that is installed in place of hte old buzz box. This gizmo winds up like
> > an
> > electric motor, has it's own compartmet (fairly large), makes plenty of
> > noise and will blow the main fuse if used while plugged into shore power.
> > Sorry, no pics as I would have to remove a panel to get to this. I'm not
> > entirely sure but I believe it was installed by Cinnabar.
> >
> >
> > --
> > Steve Ferguson
> > Sierra Vista, AZ
> > _______________________________________________
> > GMCnet mailing list
> > List Information and Subscription Options:
> > http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Steve Ferguson
Sierra Vista, AZ
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Re: [GMCnet] Oddity [message #105797 is a reply to message #105781] Fri, 12 November 2010 15:32 Go to previous messageGo to next message
Steven Ferguson is currently offline  Steven Ferguson   United States
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Registered: May 2006
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Senior Member
Thanks for all the input on this guys. I like learning something new.
Virtually everything on that coach that has been replaced, added, or worked
on has been accomplished by Cinnabar, Buskirk Rush, or Bob Lamey. It is all
I touted it to be. The PO spent $7,000 on the interior and insulation
package. The compartment that gizmo sits in was professionally built to
house it so I wonder if it was Cinnabar, Buskirk, or Lamey that installed
it.

On Fri, Nov 12, 2010 at 9:02 AM, David H. Jarvis <jarvis210@shaw.ca> wrote:

>
>
> We had "MG" sets to change AC to DC for smoother control on elevators.
> They are now using rectifiers.
> --
> "I've always been crazy, but it kept me from going insane"
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Steve Ferguson
Sierra Vista, AZ
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Re: [GMCnet] Oddity [message #105800 is a reply to message #105752] Fri, 12 November 2010 16:45 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
Karma: 7
Senior Member
Steven Ferguson wrote on Fri, 12 November 2010 06:46

Maybe not to some of you, but this is certaintly an oddity to me. The coach I recently advertised here for sale is at our Thanksgiving rally here in Benson, AZ. The new owner asked me about a device installed in the coach that makes AC our of DC. This is entirely separate from the TruCharge 40 that is installed in place of hte old buzz box. This gizmo winds up like an electric motor, has it's own compartmet (fairly large), makes plenty of noise and will blow the main fuse if used while plugged into shore power.
Sorry, no pics as I would have to remove a panel to get to this. I'm not entirely sure but I believe it was installed by Cinnabar.

--
Steve Ferguson
Sierra Vista, AZ


Steve,

Dynamotor is a fancy name for unitary motor-generator set. Unfortunately this label or MG set tell you just about nothing. This variety were also often referred to as inverter-generators, as opposed to the lower power inverters of the day that used an electro-mechanical vibrator and a big transformer.

These, very much the the old technology of the Onan, do have a considerable sense of humor for abuse like high/low voltage and overload that will toast the fancy transistors.

As you have heard, these pre-date electronic inverters. The are no longer around (like steam locomotives) because of both initial cost and high maintenance.

Some of these had a really neat mechanical governor deal that leaned on a carbon pile to control the output frequency to within a single Hertz (CPS - for the old guys) over most of the operational range. If this has that feature, it is a collector's item. If it has a beer can size housing on one end, it just might be one.

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: [GMCnet] Oddity [message #105814 is a reply to message #105752] Fri, 12 November 2010 22:20 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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Location: Woodstock, IL
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Senior Member
Sadly I remember that Cycles per Second changed to Hertz in my lifetime.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: [GMCnet] Oddity [message #105824 is a reply to message #105752] Fri, 12 November 2010 22:49 Go to previous message
Chr$ is currently offline  Chr$   United States
Messages: 2690
Registered: January 2004
Location: Scottsdale, AZ
Karma: 1
Senior Member
we also use them in the semiconductor industry to isolate sections of Ion-Implanters. In this case, we run a 208V 3ph motor connected to the generator to generate basically the same voltage, phase and freq, but there is a 2 ft long fiberglass shaft coupling them. Seems odd at first, but we need the isolation.

In an RV, I can see it for running while the main engine is running, but spinning this thing from battery power would kill that battery pretty quickly. you are basically multiplying the voltage by 10X, and drawing tons of current doing so.


-Chr$: Perpetual SmartAss
Scottsdale, AZ

77 Ex-Kingsley 455 SOLD!
2010 Nomad 24 Ft TT 390W PV W/MPPT, EV4010 and custom cargo door.
Photosite: Chrisc GMC:"It has Begun" TT: "The Other Woman"
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