I have seen many, many static phase converters built and used succesfully on
all types of motorized equiptment with the exception of air compressors. I use
one to power my 7.5hp pacemaker lathe. I have never seen the need to be
running an idler if you are only going to be operatiing motors of fractional or
up to 1 or 2 horsepower.
Mainly the only reason I built my superlarge static unit was to prove it can
be done and that it works very well. It also has alot of run caps and all
phases are within 2.5 amps of each other under load. I don't call that single
phasing at all. My father built about 12-15 STATIC phase converters for a
fellow that was moving his whole machineshop from town (3 ph power) to his home
(single phase). Since pretty much everything was not under load when started
they went the static converter route. That has been 10-15 years ago and as
could be expected they have had acouple caps release their magic smoke but no
biggie, repairs are quick, cheap and easy and no big motor sitting running
turning the ole power meter faster.
I plan on setting up a rotary unit in the near future only because a new mill
I bought really needs the cleaner power of the rotary unit, otherwise it would
be on a static unit.
Most small phase converters I have built I have little or no money in them.
They can also be used to start a rotary phase converter as well. The 7.5hp
static unit I built I had just over 100.00 in it and that was with 100% new
components.
Oh yes, one other thing I have been an Journeyman wireman(industrial and
commercial) for 17 years. My father was a locomotive electrician from the mid
50's till 1964 and then an Industrial/commercial electrician till he retired a
few years ago.
Looks like I am going to have to run down to the supply house and buy a large
lot of goodies and start making up some add-a-phase units, at a 100.00 a crack
wowwiieeee,,, Im in the money,,

good luck

tim