Using a 400hz generator

 

I have an op to aqired 115V * 90KVA genset. which runs at 400hz
I did some searching and basically understand the issues trying to get 50 or
60hz
from it,  ie not really worth the effort.
However I'm thinking of taking the output => convert to DC => feed to
Inverter to get
mains Voltage @ 50/60 hz.

The unit is old and has a 6 cyl detroit diesel. I'm hoping to use the heat
from it
to heat the pool and the inverter to power the pool pump and maybe the house
in a blackout.
The idea is to run on WVO. Since I don't need anything like 90KVA I'm
thinking of running at lower revs.
From my searches I'll guess at this time that it runs at 2400rpm (but I
could be wrong) If I ran it at say 1200 rpm,
could it produce enough to feed an inverter?
Should I worry about batteries in the system? (i'd prefer not to).
or maybe I could I just run a couple of immersion heater elements (eg from
hot water services) directly from the  400hz?
& buy a small backup genset for blackouts.

Anyone else making use of 400hz gensets?
 Appreciate any thoughts.

 

Let me tell you a story. I recently bought a Onan 10 kW generator head
from the military for $113 plus tax plus 10%, about $130. (new old
stock). Sold it to a buyer for $666.56 (ka-ching). I was worried that
the buyer did not know what he was buying, will have coupling issues,
but it turned out that he knew what he was doing. He had a similar
military generator with a 400 Hz head. His plan is to swap his 400 Hz
head for the 60 Hz head that I sold him. He swears, to my surprise,
that his 400 Hz is also a 1800 RPM model. I dunno.

So, perhaps, if you look hard enough, you may find an electrical head
with appropriate coupling and that is 60Hz.

If your "op to acquire" the generator is cheap enough, you may be able
to buy it, sell the engine separately, and sell other parts as well,
and buy yourself something nice like a smaller generator like the one
Steve Spence is using.

60 kW generator would weigh about 3,000 lbs. I hope that you have a
forklift!

i

On Mon, 21 Mar 2005 22:35:28 +1030, <richard> <richard> wrote:

 



Just for reference.
Things that you can run directly off a 115V 400cycle generator.

Resistive heaters.
Incandescent lights. (halogen, xenon, vacuum)
Compact fluorescent lights.
Large Rapid start fluorescent lights with a magnetic ballast.
(not units with a series reactor)
Universal AC/DC motors will run fine. (drills, saws)

These types of equipment can be ran with precautions taken.

Large fluorescent lights with an electronic ballast.
(pretty much the same as compact fluorescents)
Radio's and TV's should operate fine.
Computers should run fine.
Anything with a switching/rectified power supply should be fine.
The only note I have for the equipment listed above is that
Some switching supplies/TV's radios have a large shunt capacitor across the
ac input.
That capacitor is to block noise from entering, and leaving the supply.
If you hook 400Hz to that type of supply, then the noise filter capacitor
will draw excessive current, and overheat/self destruct.
Before you operate that type of equipment,
you should open up the supply on the unit,
and remove any shunt capacitors before the rectifier on the equipment,
and then the equipment will work fine on 400Hz
Or, for that mater, 10 Hz to 10Khz
And yes, it will void the warranty. :-)


The only things that won't run is induction motors.
And cheep battery chargers that use a series capacitor
to limit charging current.

 

What about microwave ovens?  I replaced the engine on a Coleman 1500 watt
generator and had trouble getting the microwave to work.  The digital
display would not even come on.  I adjusted the engine speed by using an old
battery charger.  I turned the throttle screw until the charging rate was
about the same as it was with my little Honda generator (eu2000) and then
the microwave's display came on and it was able to heat/cook.  Or was this
all a coincidence?

Is there an easy way to adjust the frequency when modifying/replacing
generator engines with common tools?  I don't have access to an oscilloscope
at the moment.

 


Buy a kill-a-watt frequency/voltage/power meter. It should set you
back $25. I have an extech multimeter that measures everything under
the sun, voltage, frequency, temperature via a thermocouple, amps,
farads, literally everything. A very nice unit. $100 takes it.

i