[Amps] Benefits of 3-phase power?

[Bill Turner]

On Sun, 16 Nov 2003 07:22:17 GMT, ka1xo at juno.com wrote:

>The everyday advantage to using 3-phase mains is smaller wire diameter and lighter motor frames for the same HP. 

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There are three other advantages:

1.  A DC supply is easier to filter, requires less C.

2.  Motors run much smoother because total current never goes through
zero.  This is especially noticeable under heavy load.  A single phase
motor is powered off and on 120 times per second.

3.  Reversing motor rotation is easy.  Just swap any two phases.

On the drawback side, you can not turn off three phase with an SPST
switch.  Also, more rectifiers are required for a DC supply.

There are probably more advantages and disadvantages but it's been a
few years.  :-) 

--
Bill, W6WRT