diesel gen set

[Anonymous-0]

purchased a diesel gen set at an auction, 4-71 engine, runs great but found its 400 hz can it be changed to 60 hz ?

 

[David G]

not easy enough

 

[buickanddeere]

Far cheaper to obtain a generator head from ebay.
Probably 100KW would be about max for the 140HP power plant.

 

[RayP(MI)]

400 hz was used by military on aircraft applications. Suspect you need to slow generator RPMs speed to change frequency. Slowing will reduce capacity of generator. Might be easier to swap out with new generator head designed for 60 hz.

 

[David G]

You will be shocked on the price of a 100kW 60HZ alternator.

 

[JMOR]

It is far more that just rpm. The generator magnetics are very different

 

[David G]

The frequency is determined by RPM and number of poles
that it is wound to.

 

[John T]

In order to change it to 60 HZ you have to change RPM and also the number of poles, this is NOT something you can mess around with in the shop and convert easily.

John T

 

[buickanddeere]

Slowing the generator from 400Hz to 60Hz will drop the output voltage to 15% of the nameplate voltage.
Probably 115V or 115/200V. Some 480V equipment too.
Thus 115V would drop to 17.25V, 200V would drop to 30V and 480V would drop to 72V.
You could rig a cob job with a 120/480V transformer and up the 30V from the 200V system to 120V.
Ain't worth the effort.

 

[wisbaker]

As a young 2ndLt I moved my branch into what had been the alert facility for the 87th FIS (Fighter Interceptor Squadron) They had been flying F106 Delta Darts, all the electrical receptacles in the bays were 400Hz. As the others have said there is not a piratical way to make it 60Hz. Hopefully you got it cheap enough to have gotten a good deal on a 4-71 Detroit

 

[Billy Shafer]

Not without spending more money than you already have.

 

[buickanddeere]

If 400Hz at 1800rpm. 60hz would occur at 270rpm but there is not way a 4-71 will operate at that those revs.

 

[greygoat]

I was in Army aviation...we had 10 KW generators
made by "Consolidated Diesel Electric", had a
4 cyl overhead valve engine that looked like a
Continental in an early,(Ford 8N size) Massy-
Fergusson..anyway they were 400 cycle, BUT to
get 240 volt 60 cycle, we ran a Motor-Generator
that took the 400 cycle input to run a large
electric motor..(10 horse ?)which was direct
shaft coupled to a generator that put out 220
volt 60 cycle AC. The motor-generator was bolted
to a steel pallet mounting that a fork lift
could move. Start looking at surplus outlets for
a motor-generator.

 

[Anonymous-0]

No. Scrap the generator and save the engine.
I worked on military generators my entire 20+ years in service. All missle systems and some aircraft used 400hz.

 

[JMOR]

(quoted from post at 08:57:47 08/14/12) I was in Army aviation...we had 10 KW generators
made by "Consolidated Diesel Electric", had a
4 cyl overhead valve engine that looked like a
Continental in an early,(Ford 8N size) Massy-
Fergusson..anyway they were 400 cycle, BUT to
get 240 volt 60 cycle, we ran a Motor-Generator
that took the 400 cycle input to run a large
electric motor..(10 horse ?)which was direct
shaft coupled to a generator that put out 220
volt 60 cycle AC. The motor-generator was bolted
to a steel pallet mounting that a fork lift
could move. Start looking at surplus outlets for
a motor-generator.

e did exactly the reverse (60Hz motor driving 400Hz aircraft generator) to obtain 400Hz to operate & test aircraft electronics that our factory built.