In article ,
what says...
On Tue, 22 Jun 2004 12:35:19 -0400, the renowned Jeff Wisnia
wrote:

KD wrote:
I have 2 machine tools both 3 phase. I have a phase converter. I have
been in the past, just pulling the 3 wires from the motor off of the
converter, and plugging in the motor wires from the other machine.
Its a bigger pain that it sounds. I am looking for some kind of swith
to just switch between the two without having to pull wires. ANybody
know what I should be looking for? Thanks for the help. if trying to
email me direct, email
Thanks

Ask your electrical supply store for a "manual double throw three phase
transfer switch" with sufficient ampacity for the heavier of the two
loads. Wire it in where you can easily reach it to throw the handle.

Lots of companies make them.

If cost is a factor and you've got a well stocked electrical junk pile,
but no transfer switches in it...... You could use a couple of three
phase disconnect switches (fused or unfused) and rig some kind of a
mechanical interlock between them so that they won't both be "on" at the
same time. It shouldn't take much more than appropriate mounting
locations and some sort of center pivoted lever to accomplish that. (No
warranty from me on an electrical or insurance inspector "buying" it
though. G)

Good Luck,

Jeff

I'd probably wire the two up and just remember not to switch both on
at once... but that would be wrong.


That's what I do with my 3 phase machines that do not have
VFDs. As long as the wiring is adequate, in most case
there's no problem starting another machine when another is
already running, with either a static or rotary converter.
In other words, I don't understand why the OP feels it's
necessary to have only one machine connected at a time.

I do have a pair of 30A motor starting switches wired as
Jeff describes above to select either the rotary or static
converter. One switch is mounted upside down and a bar
between the handles prevents both from being on at the same
time.

Ned Simmons