Dont Know What Genset I Have Help Please

[mijon]

Below is a Okeefe & Merrit Military Generator Serial # 77. It has a 25 hp motor, RPM rated at 1735, Frequency of 60, 208 V, 55 AMP, 3 Phase or single, 12.5 KW output, 4 wire, and 43.5 rated amp load per line. The overall Dimensions are 19" L X 32"W X 34 1/2" H and weighs 777 pounds

Brief History:
Purchased what believe to be Phase Converter of Government Liquidation. There was a poor description of the lot and I didn't really have a clue to what I was looking at (first mistake description is the first paragraph above). The description said Generator so I thought it was a generator or Genset. Went to pick up the lot and found out that it was definitely not what I was looking for.

What I know:

From what I think I know this is the phase converter leg of a the Genset. It is missing the power plant that goes with it. The purpose of the phase converter was to take single phase and convert it to 3 phase. There is an electric motor inside to jump the 3rd leg. The converter takes 208 volts and converts it down to the other 3 legs one of them being ground. I have very little knowledge with electrical units especially Generator, Phase Converters, etc.

Question:

1. Basically would like to know if my assumptions are correct and any other information you could give me would be very helpful.
2. What kind of practical use can I use this for.
3. What kind of power plant goes with this converter to make it a complete Genset.
4. Is there a demand for this type of Converter anymore.
5. Any other information would really help me out. (specifics of power peg leg etc.)

I have attached Pictures and description.

Thanks,

 

[Warthog]

Looks like 400 Hz unit which is just about useless to the general public.

 

[mijon]

From what I seen they used this kind of converter in the Air Force to power air planes of some sort? or Telecommunications? I know most homes use a 40-60hz but there has to be some other kind of use for a 400 hz besides airplanes.

 

[MWMULES]

Aircraft electric motors average about 5 lbs. per H.P. compared to ,[FONT=inherit !important][FONT=inherit ! important]industrial [FONT=inherit ! important]motors[/FONT][/FONT] which can be close to 100Lbs. per Horsepower. One way this reduced weight is attained is by operating at high speeds. Rpm is a function of frequency divided by the number of poles. 400 Hz induction motors operate at speeds from 6000 to 24,000 rpm through reduction gears. [/FONT]

 

[Another Ahab]

Never know; might learn something. Subscribed.

 

[gimpyrobb]

Yup, use it for lighting, resistive heat, or aeroplanes.

 

[storeman]

Also for Radars.

 

[Recovry4x4]

Follow

 

[Isaac-1]

My best suggestion is to try to sell it to your local air craft mechanic

 

[3dAngus]

Often 400hz units are sold to local airports for bigger dollar value then 60hz units to the general public, but the market is so much smaller so it is difficult to make the sale.
You can make double the value if you can find an airport owner in need.

 

[SCSG-G4]

Motor-generators are also used in data centers for powering mainframe computers. Input is the standard electricity that comes to a wall socket, with all it's sags and spikes, noise and harmonics to power the motor part. Output comes from the generator part - no sags, no spikes, no 'noise', no unwanted harmonics, etc. Compared to 60 hz single phase, 400 hz three phase almost looks like two parallel lines of power, at the peaks, not a series of hills and valleys.

 

[1800 Diesel]

Jon,

On Navy ships similar units were known as M-G sets or motor-generator--these used to provide 400hz current for aircraft (& other 400hz components on the ship) as others have noted. Basically, where abundant 3-phase power was available, whether shipboard or shore, the MG sets (or frequency converters) were used vice a diesel-driven 400hz unit. If you were looking for standby power for your house or shop (as you already know) this was definitely not the ticket.

Like others have said, resistive loads & incandescent lighting can be powered by 400hz power, but since the prime mover on this unit requires 3-phase 208V feed, you would still need a 3-phase generator to power the 25 hp drive motor. I expect the draw amperage would well exceed the 55 amp run amps of the drive motor--IIRC by a factor of 2 or so?

Oh well, lesson learned for this one. Hopefully you'll be able to locate a suitable customer in need of 400hz power.

Bottom line--sell it if you can.

Kevin

 

[Another Ahab]

Jon,

On Navy ships similar units were known as M-G sets or motor-generator--these used to provide 400hz current for aircraft (& other 400hz components on the ship) as others have noted. Basically, where abundant 3-phase power was available, whether shipboard or shore, the MG sets (or frequency converters) were used vice a diesel-driven 400hz unit. If you were looking for standby power for your house or shop (as you already know) this was definitely not the ticket.

Like others have said, resistive loads & incandescent lighting can be powered by 400hz power, but since the prime mover on this unit requires 3-phase 208V feed, you would still need a 3-phase generator to power the 25 hp drive motor. I expect the draw amperage would well exceed the 55 amp run amps of the drive motor--IIRC by a factor of 2 or so?

Oh well, lesson learned for this one. Hopefully you'll be able to locate a suitable customer in need of 400hz power.

Bottom line--sell it if you can.


Kevin

A few here (mijohn, MWMULES, gimpyrob) mentioned it's utility for aircraft.

And I know a coupla-three pilots (civil aviation: Fl, MT, and one in VA) and they are all pilots in their "sunset" years with the time and "re$ource$" that makes their hobby possible:

- this profile (time and re$source$) fits the background of a lot of the civil aviation crowd

- my point is you can likely find a ready market for your generator (if you WANT to let it go), by dropping in at any of various municipal airfields around you and asking around/posting on bulletin boards.

- Municipal Airfields: there are always more around (AND usually closer than you think) than you ever imagined. It's like getting a new model of car and all of a sudden noticing the same model everywhere you look: until you focus on it, you never notice.

Go for it! You should be good.

I got skin in this game now, so please let us know what you decide to do.

 

[epitts]

You mite try selling it at http://www.barnstormers.com/