Re: Home shop power for a big machine

Seems to me if you ran the spindle on a VFD and always started at low RPM
you could avoid most of the start-up current draw. If you make sure your
local breaker pops before the one on the pole, you can keep the power
company out of your pants as well. If you don't have adequate power from the
pole, there is no point lusting over a big rotary converter that is going to
pop your breakers every time.
--
Phil Mattison

----- Original Message -----
From: Jim Fleig - CNC Services <jim@...>
To: <CAD_CAM_EDM_DRO@yahoogroups.com>
Sent: Wednesday, December 31, 2008 8:59 AM
Subject: Re: [CAD_CAM_EDM_DRO] Home shop power for a big machine


> Hi Roger,
>
> Just a thought: the power you may need to run the machine may be much
lower than the power you will need to start the machine. Most three phase
motors have a surge of power that starts the motor and then the current draw
drops way down while the motor runs at its rated rpm. It may be more
helpful to try to address the question about starting the machine. After
the machine is started, then it may take very little power to run the
machine to do what you would like to accomplish.
>
> Happy New Year!
>
> Jim Fleig
> CNC Services
>
> machine tool service from casting to control
>
>
>
> ----- Original Message -----
> From: vrsculptor
> To: CAD_CAM_EDM_DRO@yahoogroups.com
> Sent: Wednesday, December 31, 2008 10:10 AM
> Subject: [CAD_CAM_EDM_DRO] Home shop power for a big machine
>
>
> I was lusting over a big VMC that would never fit in my home shop and
> got to wondering about power. The machine's data plate says 230 volts
> 3PH @ 80 AMP's, 18KVA. It has a 15 HP spindle.
>
> I could use a rotary phase converter to generate the three phase but
> don't have anywhere near 80 AMP's available. 18KVA/750 watts equals a
> 24 HP phase converter.
>
> If you where using this machine in a hobby environment and not trying
> to get production feeds and loads how small of a phase converter could
> you get by with?
>
> Roger
>
>
>
>
>
> [Non-text portions of this message have been removed]
>
>
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