What's needed to wire up a rotary 3ph converter?

Rotary converter will be installed in my garage and used to run lathe & mill (one at a time). Supply will be dryer circuit of 30A 220v. Wiring up is straightforward, but what switch(es) and fuses should I use?
The converter no switch or fusing. The lathe and mill do not have fusing either.
Is the 30A breaker sufficient to protect the entire setup? Is one 2-pole disconnect knife switch (with 20A fuses) sufficient to protect all?
Suggestions?
Thanks.

On 4/9/2011 10:43 AM, Paul Conners wrote:
  Quoted Text Here  
Not sure how your phase converter is setup up, but I strongly suggest you make sure it won't start back up on its own in the event of a power failure and return to power. Could be very dangerous. Make sure you ALWAYS have to manually start the phase converter.

  Quoted Text Here  
I agree, use an electric contactor instead of just a manual switch. Set it with a START/STOP set up.
You sould expect about 180 amps starting current.
i

  Quoted Text Here  
Overvoltage?

wrote:
  Quoted Text Here  
You are truly a numbskull, Gunner.
Since, surprisingly, your house hasn't ( yet ) caught fire...
  Quoted Text Here  
Zoom....
Hmmm...
In the case of my installation, the OUTPUT side is into a 20 circuit 3ph breaker panel and if I were to put a 30 amp fuse there at the output it would barely allow even running the air compressor let alone the rest of the machines that are wired onto the buss...
--FWIW the input side is a 125 amp breaker which feeds single phase to the idler which is a 50 hp Toshiba Hi E
BTW, whoever it was here that mentioned using a contactor and definate start /stop circuit to forbid auto-restart upon power fail or brown-out is spot-on..
--You definately want the magnetics to drop input power altogether in this instance otherwise you will get huge HV transients sent down the line--not good if you have any computers or equipment that uses varisters to protect against spikes.

Gunner can count them on his fingers and toes at customer sites. Lots of them in his work area.
I got one from him and have it running in my shop on 220 and 3PHase contactors. I have some 220 contactors if anyone needs one or two.
Martin
On 4/10/2011 1:26 AM, PrecisionmachinisT wrote:
  Quoted Text Here  

  Quoted Text Here  
Most of them are out of business now....
Hiring him probably was a major contributing factor.
  Quoted Text Here  

ELI the ICE man.
Voltage leads current in Inductive Current leads voltage in Capacitive circuits.
Rotaries are inductive. Motors are inductive. The rotary is somewhat balanced over a range. But motors are not.
Starting and stopping motors causes surges and spikes. The impedance quells some of that and enhances others.
Martin
On 4/9/2011 8:24 PM, Ignoramus28444 wrote:
  Quoted Text Here  

typed in rec.crafts.metalworking the following:
  Quoted Text Here  
    Just for your amusement. Friend reports that one of the main machines is down at work. It had been acting up, errors in Z, and last week - it tripped the breaker. Somehow, he didn't know, and I couldn't follow the explanation on possible causes (out of my area of understanding.)     1400 amp, 3 phase, 430 volt service. tripped the breaker. "Ooops".
    Good news - with that machine down, he can get Holy Week off.
    Worse news, the supply factory for the inserts for the 2 inch face mill which does the majority of their work - is dun got washed away. So, they have about a week's supply on hand and then .... they do not even have enough on hand to cover wheel they scramble for a replacement.
tschus pyotr

on Sat, 09 Apr 2011 15:28:52 -0700
  Quoted Text Here  
1400 amp at 430 ( 430 ? ) is enough to power a small city here where I live in rural Wa State
I have never encountered a machine tool that uses that much power but for academic purposes let's just run the numbers....
1400 x 430 = 602,000 kva ( WATTS at PF 1 )
= 4,289.4 horsepower....
  Quoted Text Here  
Well, since it's unlikely they can afford the power bill anyways...
  Quoted Text Here  
Sounds to me like the place is run by total idiots--and it's readily apparent that you would probably fit in very well there.

  Quoted Text Here  
This video shows at slow speed how hex cutting is achieved:
<
http://www.youtube.com/watch?v=-9jMN9Bgg6g&NR=1

Dave

pyotr filipivich wrote:
  Quoted Text Here  
The breaker is a GFI breaker and is tripping on a short to ground on the machine, not necessarily drawing a lot of amps but on the unbalanced flow of current.
John

in rec.crafts.metalworking the following:
  Quoted Text Here  
    Okay. He said that they don't have Ground Fault Interrupts on that setup, but ... who am I to say?

pyotr filipivich wrote:
  Quoted Text Here  
I believe that on newer 480 service disconnects Ground Fault interrupts are required over a certain amperage. Newer would be in the last fifteen years or so.
John

in rec.crafts.metalworking the following:
  Quoted Text Here  
    I'll ask when I see him next.
  Quoted Text Here  

Yes -
I have one in my shop - generates 3-phase (one a little wild) and then I step up the 220 to 380v and send it to my grinders.
I have a circuit - you can look at mine and strip down.
I have circuit breakers and contactors I have a box that holds them - pro grade - and a hand plug that plugs into my 220 plug in the shop. (I have a 30x30 building) From the box I have 22o on a second local breaker - and a contactor that switches 220 to the rotary. Rotary comes back through a breaker to a contactor and then to distribution sockets.
I have extension cords on mine - 3 phase ones - but some want to wire and use more often than I. My grinders are 1% use. Want to get rid of one.
If you want the design - I might be able to find it - and send you a copy.
Martin
On 4/9/2011 12:43 PM, Paul Conners wrote:
  Quoted Text Here