[AMPS] 3 phase transforers and single phase

[jeff@wa1hco.mv.com (jeff millar)]

I have an old metal lathe with a three phase motor.  In order to get three
phase power to drive the motor I got a 5 HP three phase motor from the junk
yard.  I connected 240 across two of the phases and it generates the third
phase just because it's spinning.  It doesn't want to start by itself, it
just sits there humming and smelling very hot.  To start it, I just turn on
the power and give the shaft a flip with my foot and it takes off.  If you
need more power, just connect multiple motors in parallel.  When I start or
reverse the lathe, the motor on the floor hums louder and jumps around a
bit...very cool..

The voltage generated by the third phase runs a bit less than the the other
two. Probably not a problem in practice.  This trick should work very well
to generate three phase power for transformers and rectifier systems.

jeff, wa1hco

----- Original Message -----
From: Peter Chadwick <Peter_Chadwick@mitel.com>
To: <amps@contesting.com>; 'William Fuqua' <Wlfuqu00@pop.uky.edu>
Sent: Thursday, April 19, 2001 2:29 AM
Subject: RE: [AMPS] 3 phase transforers and single phase


>
> Bill asked:
>
> >Recall the discussion of running a 3 phase power supply
> >off of single phase mains?
>
>
> The model engineering people  running 3 phase motors  use either
> capacitive splits (so not true 3 phase) or inverters, or (a very few),
motor
> generators.
>
> My inverter (for the mill and the lathe) can be bought for about $250 over
here,
> and
> will provide variable frequency drive (thus variable speed) for a 1hp
machine -
> it's
> about 850 watts continuous output. It's in a box about 6 inches by 5
inches by
> 3 inches. Output powers up to abt 3kW are available from large units.
>
>
> 73
>
> Peter G3RZP
>
> --
> FAQ on WWW:               http://www.contesting.com/FAQ/amps
> Submissions:              amps@contesting.com
> Administrative requests:  amps-REQUEST@contesting.com
> Problems:                 owner-amps@contesting.com
>
>


--
FAQ on WWW:               http://www.contesting.com/FAQ/amps
Submissions:              amps@contesting.com
Administrative requests:  amps-REQUEST@contesting.com
Problems:                 owner-amps@contesting.com