"Nick Mueller" wrote in message
...
Jerry wrote:

I considered that when one motor is
running after being easily "spun up", it becomes a Rotary Converter for
the other two motors.

You forgot, that the motor's shafts aren't connected. This is a saw (or
such) with three separate motors.
You have to draw a diagram how the three legs of the three motor are
connected. You don't want?
I'll describe it with words:

L1, L2, and L3 are the phases. M1, M2 and M3 are the motors.
L1 is the only phase available, so you connect it to M1L1. M2L1 and M3L3
are
open, because we don't want to let them run. OK so far?
Now the voltage generated in M1L2 and M1L3 goes where? Nowhere, because
they
are not connected on M2 and M3 (because we don't want to let them run).

Now we let run all three motors at the same time.
Connections:
M1L1 to M2L1 and M3L1
M1L2 to M2L2 and M3L2
and
M1L3 to M2L3 and M3L3

Now the voltage generated in M1L2 is feed into M2L2 and M3L2 (same for
L3).
But at the same time M2 and M3 generate voltage at L2. Now do you really
think that one motor can drive L2 and L3 of the two other motors and at
the
same time doesn't lose any energy?
Note that I disregarded losses and was talking about an ideal machine.


Do you actually think any of
the information I have posted is wrong?




Absolutely. :-)

You might take some time to think about this
Rotary Converter stuff before writing about *my* errors.

This ain't a rotary converter!
OP cite:
| ... is looking at buying a Felder combination woodworking
| machine with 3 4kw motors in 3 phaze ...


Nick
--
The lowcost-DRO:
http://www.yadro.de


Nick, this is silly. You are smart enough to figure this system out.
Why do you insist in not trying to understand. This guy with the three
motor machine only wants to run it on single phase. He doesnt need a
ROTARY CONVERTER. He even told us that he is planning on using a
http://www.grizzly.com/products/Stat...-to-7-HP/G5843.
That is a Static Phase Converter.

I have tried to draw your attention to the fact that each of the three
motors will have three wires, and he will have single phase power supplied
to only two of those wires in each motor. This is not complicated. The
machine has three independent 3 phase motors. Each is driven with single
phase.

I thought it could be beneficial that when one 3 phase motor is spinning
it provides a 3 phase voltage across it's three legs. That makes the first
motor to act as a rotary converter for the second motor.

I thought it would help the OP to know that his 3 phase motors will
deliver nearly full name plate rated power to their loads even when it is
powered by single phase to only two of it's three leads.

You wrote that I dont want to draw a diagram of this machine. You cant
either unless you know something that isnt written in this thread. I dont
know if the motors run simultaneously or in sequence. How do you know how
the motors are wired??? I ask you to think about what you write before you
complain about any mistakes *I* have made. Or, of course, you are invited
to tell me precisely where I have written something that *is* in error.

Jerry