Re: Phase converter questions

Concerning rotary phase converters vs VFD and static converters there
are many conciderations:

- the benefits of a the static phase converter and VFD are the gains in
efficency and the quite operation
- most VFD's have the added benefit of allowing you to control the speed
of the spindle motor
- an important note is that VFD's and static phase converters can only
run one motor at a time; they must be connected between the wall power
and the motor leads
- a rotary phase converter can run multiple motors at once and is the
only converter that can run a 3 phase welder
- there is one leg that will appear to run at a higher voltage on a
rotary phase converter, this effect will disappear once the converter is
under load.

The legs of a rotary phase converter need to be balanced very well if
you are running CNC equipment with it see the information here
http://www.phase-a-matic.com/CNCPac.htm.

I use a 10hp rotary phase converter with my old Gorton mill because my
spindle and feed motors are 3 phase.

The reduced power consumption and increased control is why most water
and air control equipment is being upgraded to VFD's.