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  1. well i was talking about op's lathe, so i...

    well i was talking about op's lathe, so i interpreted your post a bit differently....
  2. you could probably push the volts per hz up to...

    you could probably push the volts per hz up to 50% higher than the transformer was designed for starting purposes only, but out of the box the initial default 20% voltage at zero hz is going to blow...
  3. you should have no problem running a transformer...

    you should have no problem running a transformer from a vfd, but you must program the vfd for linear volts per hz, otherwise you will saturate the transformer at turn on. this is most likely the...
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    Maybe a 4 pole contactor, it's coil rigged up to...

    Maybe a 4 pole contactor, it's coil rigged up to an E stop normally connected switch and small 24vac transformer.

    3 poles are post vfd connect the motor to vfd.

    The 4th pole is in series with...
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    Or a bad belt.. the belt is running in the V of...

    Or a bad belt.. the belt is running in the V of the pulley but its on the Flat of the counter shaft pulley correct? so if you've got a belt that has a thick spot or a thin spot in it, the belt...
  6. the secondary you are feeding with 240 appears to...

    the secondary you are feeding with 240 appears to be rated for 33 or 35 amps. so, on the order of 13Kva.

    since the voltage is lower and you're not using the full primary winding, you may be able...
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    the spindle with its regenerative drive is a VFD...

    the spindle with its regenerative drive is a VFD if its a 3 phase motor.

    If you've got a dc motor spindle then the proper terminology is to call it a dc motor controller. or a 4 quadrant dc drive,...
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    Depending on where, and how the phase perfect...

    Depending on where, and how the phase perfect measures its output current, you may be able to solve the problem by adding an additional line reactor (3% should do it) to the output of the phase...
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    You could try cutting the gear with mod 1 cutter,...

    You could try cutting the gear with mod 1 cutter, then rotate the gear a few degrees on the dividing head and cut it again.i think they call that a profile shift which would normally increase the...
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    Talk to the person you bought it from. That is...

    Talk to the person you bought it from.

    That is a delta wound motor, it should not be a problem.

    there appear to be some differences thermally between Y and delta motors when used as a rotary...
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    that is the kind of shift you would get from...

    that is the kind of shift you would get from cutting two gears of different teeth to fit on the same center distance.

    can you post a photo?
  12. find the neutral of your motor and connect it to...

    find the neutral of your motor and connect it to ground, two legs go to your two existing phases.

    the motor will start on its own, and run. you can run machines this way and you can get about half...
  13. the issue is creep. modern aluminum alloy has a...

    the issue is creep. modern aluminum alloy has a little bit of silicon in it and is something like 58% iacs resistance and isn't a problem provided you use deox grease on the terminals.

    the second...
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    most dual voltage motors are wound with two wires...

    most dual voltage motors are wound with two wires in parallel "in hand" so when you connect them for 480 volts every single wire everywhere in the motor has 240 volts between it and the next wire....
  15. all you need is two 240:240v single phase...

    all you need is two 240:240v single phase transformers and you've got 3 phase when hooked up correctly.
  16. .4 volt peak would correspond to .01 ohms...

    .4 volt peak would correspond to .01 ohms resistance of the filter cap for a 40amp current.

    40 volts is more believable corresponding to a 100:1 probe and complete lack of input cap
  17. is there a possibility these units are drawing...

    is there a possibility these units are drawing asymmetrical load from the mains, a net dc current of even a few amps?

    what clues me into this is the 60hz hum getting louder. it should stay the...
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    that's quite a shift. are you sure its not...

    that's quite a shift. are you sure its not module 1.25 or could it be 20 or 18 diametrical pitch?
  19. If the motor is a synchronous motor it might help...

    If the motor is a synchronous motor it might help but only according to the resistance of the vfd and the impedance of the motor.

    If you can program the vfd to drop the voltage and allow the idler...
  20. in addition to the method described by SAF, ...

    in addition to the method described by SAF,


    you can acquire the hidden star point of your 415 volt motor (if you have a 6 wire motor it is not hidden)

    and connect the star point to your...
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    according to the backlash on the adjusting screw...

    according to the backlash on the adjusting screw and the slot in the gib and flange on the adjusting screw, which should add up to as little as practically possible. but if its >.025" then i agree...
  22. Just plug it in and run it. Monitor the motor...

    Just plug it in and run it.

    Monitor the motor temperature and amps. If they are too high, buck the input voltage down to 200 volts and try again.

    Also you can increase the motor's run...
  23. Coil up 100-200 feet of whatever you can get that...

    Coil up 100-200 feet of whatever you can get that can handle the current, say 1 gauge aluminum, 6 gauge copper.. on the input of the phase perfect. coil both lines together but the direction of one...
  24. You can program a 230v vfd for 230v 35hz and run...

    You can program a 230v vfd for 230v 35hz and run your motor and get full torque up to about 2/3rds of nominal rpm, and you'll have no problem if you don't need a lot of power, you can get about half...
  25. Short the brushes together and push current...

    Short the brushes together and push current through the field.
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