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  1. Replies
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    1,737

    Rewire the motor for delta and run it from a 480v...

    Rewire the motor for delta and run it from a 480v vfd reprogrammed for 377vac/60hz

    Or just run it from a 480v vfd programmed for 480v 48hz. Youll get full torque up to 48hz


    You can run a...
  2. Replies
    3
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    236

    Try adding a 20 or 30hp 5% line reactor after the...

    Try adding a 20 or 30hp 5% line reactor after the phase perfect, then add 100uf x3 caps after the line reactor. Delta connected.

    The phase perfect can supposidly direct online start a motor equal...
  3. Replies
    43
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    2,204

    Bolt the gate post to a flange set in the cement....

    Bolt the gate post to a flange set in the cement. In the event the soil moves you can shim the flange
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    506

    fatigue limit for the cast iron bull gear is on...

    fatigue limit for the cast iron bull gear is on the order of 40 foot pounds of torque, which is why those lathes shipped with a 1/3rd hp motor, which is all they can deliver, and its about how much...
  5. Replies
    79
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    3,853

    don't bother. repair the tank then hydro test it...

    don't bother. repair the tank then hydro test it yourself and put it back in servive. pile sand bags around it for liability purposes.

    funny thing is, would cost you more to pay someone to fill...
  6. Replies
    13
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    829

    Ripple current rating matters more. Put a...

    Ripple current rating matters more. Put a thermocouple on the cap and monitor its temperature. Heat drives the water out and the capacitor fails. Sometimes explosively.
  7. My guess is a fan has failed if indeed it is a...

    My guess is a fan has failed if indeed it is a wound rotor motor with resistors inside a box.

    Does the motor sound differently at a different speed? If one of the resistors is open circuit the...
  8. Replies
    40
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    2,448

    you don't need to tell the vfd how many poles...

    you don't need to tell the vfd how many poles there are. what other settings are you changing?
  9. Replies
    65
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    4,947

    re-work the o-ring sliding seal to include more...

    re-work the o-ring sliding seal to include more than 1 oring such that the volume of helium lost is less than the cost of fucking up the tube by welding it.
  10. Replies
    30
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    1,148

    it looks to me like the motor's 3rd phase was...

    it looks to me like the motor's 3rd phase was left connected to the incoming power. you can use either 2 and 4, or a and b, for the other two phases.

    verify that you have electrical continuity...
  11. Replies
    27
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    1,603

    250 or 260 volts didn't kill your motor. my...

    250 or 260 volts didn't kill your motor.

    my guess is you dropped a phase and that is why the motor didn't start and was hot.

    i'm also guessing your motor has an internal thermal circuit breaker...
  12. Replies
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    707

    Try draining it and filling it with an agressive...

    Try draining it and filling it with an agressive solvant

    Another possibillity is you have some swarf in there
  13. Two of them can be higher than the mains when...

    Two of them can be higher than the mains when measured in delta. Measure the voltage from the generated phase to the neutral of the 120/240v supply and it should be 208. The phae perfect gemerates a...
  14. Replies
    24
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    1,051

    1/3rd hp is the limit for the cast iron bull gear...

    1/3rd hp is the limit for the cast iron bull gear at slowest speed of 40 rpm.

    Other than that you could use a larger motor, but my guess is your starting system has failed or the motor is wired...
  15. Replies
    40
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    2,448

    A vfd typically employs regenerative braking down...

    A vfd typically employs regenerative braking down to say 20% of nominal rpm, below this it will employ dc injection.

    This may account for everything observed
  16. Replies
    40
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    2,448

    The stopping time is longer because the vfd has a...

    The stopping time is longer because the vfd has a fixed hz per second decelleration rate. Read the manual and change the settings
  17. Replies
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    1,892

    That is a very nicely rewound motor, reconnect it...

    That is a very nicely rewound motor, reconnect it properly for 3 phase.
  18. Sure you have the right oil? ...

    Sure you have the right oil?

    http://www.racingtheexocet.com/wp-content/uploads/2016/07/Oil-Viscosity-Scale.jpg

    I would not waste time messing with the motor. Run it longer and figure out where...
  19. Replies
    2
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    475

    as long as the current flowing through the 24v...

    as long as the current flowing through the 24v winding is less than 30 amps you are not exceeding the rating of the 750va transformer. or for a 32v transformer, 23 amps.

    as for the ultrasonic...
  20. Replies
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    1,892

    It could have been rewound. Need to look at the...

    It could have been rewound. Need to look at the relative size and spacing of the three coils.

    Metal strap holding switch on does not appear original.


    What are the no load amps when running?...
  21. Could have been scraped with an angle grinder....

    Could have been scraped with an angle grinder. What is the radius of those scratches?
  22. Replies
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    1,892

    starting that motor, with a cap in series with...

    starting that motor, with a cap in series with the start winding from the 3 phase RPC is electrically worse than leaving the motor connected single phase the way it was intended. the capacitor...
  23. Replies
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    1,892

    So you have an rpc. It will be about 208 volts...

    So you have an rpc. It will be about 208 volts from the generated leg to thr neutral of your 120/240v single phase supply.

    If you use an auto transformer of the correct ratio (to be determined)...
  24. Replies
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    1,857

    you are correct. part of the reason reason 6...

    you are correct.

    part of the reason reason 6 and 8 pole motors have more inertia is because the length to width ratio of the pole face increase, due to dimensional constraints (no one wants to...
  25. Replies
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    1,245

    You need to connect the x0 "neutral" of the auto...

    You need to connect the x0 "neutral" of the auto transformer to the y neutral point of the rpc. (T 4 5 6 for a 9 wire motor)

    While it would be better if you could get to both y points of the rpc,...
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