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From: josh@happym.WA.COM (Joshua_Putnam)
Newsgroups: sci.electronics
Subject: Re: 1 phase to 3 phase conversion
Keywords: phase conversion
Message-ID: <3008@happym.WA.COM>
Date: 10 Apr 91 20:18:00 GMT
References: <1991Mar28.191005.1653@rodan.acs.syr.edu> <3613@polari.UUCP> <4725@osc.COM> <1991Apr9.004732.8605@apex.com>
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Organization: Happy Man Corp., Vashon Island, WA
Lines: 27

In <1991Apr9.004732.8605@apex.com> chuckh@apex.com (Chuck Huffington) writes:

>Rotary converters are not that hard to get.  They aren't free but they
>aren't that expensive either.  I've seen some pretty cheap solid state
>stuff, but have never tried one.  I have third hand reports that they
>are not very reliable.  The rotary ones are.  The cheap solid state ones
>also only work on lightly loaded motors (<75% load).

>As I recall a rotary unit to run a 7hp motor will weigh about 100 lbs and
>cost under $1000.

Since I just happen to have my J&L catalog handy:

A solid-state phase converter for 7.5 hp, good for 75-85% loading with
"limited" duty cycle costs $279 and weighs 17 lbs.

A rotary phase converter capable of running one 7.5 hp motor and a total of
20hp load costs $1103 and weighs 200 lbs.  This is the manufacturer's
recommended loading, and may be conservative so that you could get by with a
smaller unit.  I don't know, since I don't use one of these myself.

I have seen used rotary converters in this size range sell for as little as
$100, but I don't know what condition they were in.
-- 
 Josh Putnam            josh@happym.wa.com              206/463-9399 ext.102
 Happy Man Corp.   4410 SW Pt. Robinson Road   Vashon Island, WA  98070-7399
 SOLID VALUE, the investment letter for Benj. Graham's intelligent investors