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  1. Thread: Converter repair

    by JST
    Replies
    9
    Views
    386

    The run caps are dependent on the load to some...

    The run caps are dependent on the load to some extent, so as long as it runs the load and does not have excess voltage unloaded, the value is not critical, and as noted the run caps are not even...
  2. Replies
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    755

    Coil location is not a big deal, coil does not...

    Coil location is not a big deal, coil does not need to be right up at the machine. This is waveform shaping, and not RFI filtering.

    Ideally would be a sine filter on the output of the VFD, but...
  3. If you just have to get the rotor out, you can...

    If you just have to get the rotor out, you can machine a steel "follower" or "keeper" that fits over the shaft and goes in as the rotor comes out.

    The magnet strength issue is there, but if you...
  4. Replies
    17
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    1,327

    VFD to Power Supply Trouble...

    VFD to Power Supply Trouble

    Post 12, I believe
  5. Replies
    15
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    755

    https://www.automationdirect.com/adc/shopping/cata...

    https://www.automationdirect.com/adc/shopping/catalog/drives_-a-_soft_starters/ac_variable_frequency_drives_(vfd)/vfd_accessories/ac_line_reactors/lr2-47p5

    model # LR2-47P5

    Cost yah under a...
  6. Replies
    55
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    2,019

    My answer would be "both". Ammeter to get the...

    My answer would be "both".

    Ammeter to get the torque producing current maximized (under load the power factor is not an issue in the same way)

    Voltmeter to make sure things do not get out of...
  7. Replies
    15
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    755

    I do not know if "a ferrite core inductor" would...

    I do not know if "a ferrite core inductor" would work. Depends on the inductor.

    Inductors have a "saturation point", an amount of current at which the core cannot carry any further magnetic...
  8. Replies
    55
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    2,019

    A voltmeter is the same. It reports no more...

    A voltmeter is the same. It reports no more information than the clamp ammeter.

    "Phase" is always "with respect to" something else, it is a "phase relationship", so OF COURSE you need to sense...
  9. Thread: Bench Master

    by JST
    Replies
    6
    Views
    1,594

    I have one. The "top eye" is probably...

    I have one.

    The "top eye" is probably referring to the overarm bracket that goes on the body of the spindle carrier. You'd take out the spindle carrier to remove the overarm clamp setup....
  10. Replies
    15
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    755

    Your problem is probably pulse -related. been...

    Your problem is probably pulse -related. been there seen it done that, threw out the t-shirt.

    The current at 50 Hz input is 4A, but the VFD puts out pulses at a considerably higher frequency...
  11. Short story is it does limit volts when there is...

    Short story is it does limit volts when there is a motor load on it. With no load it simply does not work at all, it needs the load.

    You change the resistor according to the table they give you ...
  12. Replies
    8
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    597

    It's not the ideal way to start scraping, but it...

    It's not the ideal way to start scraping, but it is do-able.

    Overlaps put a premium on being able to "read" the prints, and on checking "hinging" a lot. I think it is still easy to get in...
  13. Replies
    19
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    1,840

    It is rather good. A little light on the actual...

    It is rather good. A little light on the actual theory of operation, but otherwise good.
  14. A simple method is to just use a much larger than...

    A simple method is to just use a much larger than required idler. It will generally give better performance on different loads than a capacitor-adjusted RPC.

    If you really will have just ONE...
  15. Replies
    55
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    2,019

    Jim, the data you get from ANY test has to be...

    Jim, the data you get from ANY test has to be used according to what it is.

    Most motor questions of the type you mention are simply due to not knowing how motors work.

    The meter does not...
  16. Replies
    3
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    302

    You might want to see if you can power up just...

    You might want to see if you can power up just the control voltage, disconnected from power lines, and then check continuity with the meter, checking also to see that the appropriate ones close and...
  17. T canis is more common than T cati Same story...

    T canis is more common than T cati Same story either way.:D

    They are not the least bit related to wires and motors, though..... let's not get too far off topic
  18. If I had to tell you the dumb shit stuff I have...

    If I had to tell you the dumb shit stuff I have done over my life so far, that I knew better than....well, I would not want to..... just leave it there!

    If you have never messed up, then you...
  19. The subpanel for a 480V corner ground is normally...

    The subpanel for a 480V corner ground is normally different, since a 480 wye has 277 to neutral/grounded conductor, but the corner ground has 480V. That pops you to a new level of "voltage to...
  20. As a rule, you do what the NEC says, UNLESS your...

    As a rule, you do what the NEC says, UNLESS your local jurisdiction says to do something different.

    Usually local grounding is reserved for agricultural outbuildings served from a remote panel...
  21. Replies
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    2,019

    Even my old "Amprobe" meters can be switched to...

    Even my old "Amprobe" meters can be switched to be voltmeters. Having the functions as two separate meters definitely has the advantage that you can correlate voltage and current readings.

    I...
  22. Replies
    55
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    2,019

    Heh.... I think you are running out of...

    Heh.... I think you are running out of arguments.

    Using an ammeter is not the same as thinking in purely DC terms. Especially if it is an AC ammeter;)

    A voltmeter will not tell you how hot a...
  23. Replies
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    1,656

    Found some info on the painting. Article says...

    Found some info on the painting. Article says it is not steel, but puddled iron, and that painting takes 18 months, done by hand with brushes.

    Painting and color of the Eiffel Tower - OFFICIAL...
  24. Replies
    55
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    2,019

    Or use the one on the 7.5 to start an idler. ...

    Or use the one on the 7.5 to start an idler. Depends on the HP range that covers, but a static converter plus a motor makes a rotary.

    Unfortunately, Phase-a Matic seem to have a 4 to 8HP and an 8...
  25. Replies
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    2,019

    Yes. And that locked rotor current/kVA is what...

    Yes. And that locked rotor current/kVA is what is marked on the motor as the inrush "class" code in kVA per HP.

    When running, the "effective voltage" is line voltage - back EMF, and is what...
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