At 05:02 PM 7/5/00 +0200, you wrote:
>Does anyone know how to use an three-phase motor with a singelphase source?
>I have heard that a few capasitors does the job.
>Is this correct?
>If this is true, how do I connect them, and how do i calculate their
>capasitance and voltage?

Yes it is possible, not very efficient. Do a web search for "static
phase converter". Capacitor size is in the 100's of uF range (big).
You should use a cap rated for motor run applications, and for the
at least the full AC line voltage. You will lose some HP in the
process.

You can also use a rotary phase converter or a VFD (not a vacuum
fluorescent device, but a variable frequency drive). The latter
is a AC->DC->AC converter that will allow you to alter the output
voltage and frequency to the motor.

A rotary phase converter is a relatively large 3-ph motor that just
idles and generates the three phases from the terminals. You can use
a static phase  converter to get it going or find some (safe) way
to spin the shaft.

Best regards,

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