On 9/28/2010 9:10 AM, JosephKK wrote:
On Tue, 21 Sep 2010 08:53:30 -0500, wrote:

On 9/21/2010 8:34 AM, JW wrote:
On Tue, 21 Sep 2010 08:34:40 -0400 wrote
in Message :


wrote in message
...

I need to convert 115 vac 60 hz to 115 vac 400 hz 1 and 3 phase, 12 - 15
amps and 26 vac 400 hz single phase at a couple of amps. I want to
simplify the mess I spread around on my bench when I need 400 hz. I'd like
a single unit that gives me what I want. Is there a fairly simple way to
do this?

Dan, U.S. Air Force, retired

Used to be, we'd use a cobbled up dynamotor. Perhaps you could use your
connections to find a surplus ground support power supply. (Most of us know
that 400 Hz is used in airborne systems.)

I believe ships use 400Hz as well.

The mess to which I refer uses a dynamotor for single phase 115 vac,
a solid state 3 phase 115 vac and a solid state 26 vac. The 115 power
supplies require 24 vdc and the 26 vac requires 12 vdc. The dynamotor
handles the current required for test equipment, the 3 phase inverter is
good for a couple instruments and the 26 vac is for synchro excitation.
I rarely need the 26 vac as a stand alone. I have seen bench supplies
that provide what I require, but I'd rather not spend the kilobucks.

Normally the mess isn't a major problem, but my 3 phase inverter just
isn't giving me what I need.

As for ships, I have no idea, but I do have some U.S. Navy synchros
that use 60 hz. The reason aircraft use 400 hz is to save weight,
something Navy boats shouldn't be as picky about.

Dan, U.S. Air Force, retired

Back in the early 1970s the desteoyer i was on used some 400 Hz but it
was less than 5% of the total power distribution. A lot for synchros
at the entennas and such, some more for fancy electronics where it
provided a size advantage for the power transformers (to pack more
in).

I have no idea what the Navy 115 vac 60 hz synchros I have were
intended for. I just use them for demonstration purposes.

I was in special ops and spent some time at sea on Navy helicopter
assault boats. I have a feeling the natives would have taken a dim view
of me poking around.

Dan, U.S. Air Force, retired