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  1. Replies
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    1,655

    That is a reasonable estimate. However, it...

    That is a reasonable estimate.

    However, it does not seem as if it is reasonable for the lift to be designed so that it requires every possible amp of current to get itself started, especially when...
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    1,655

    Yeah, this is an electrical subforum, but this...

    Yeah, this is an electrical subforum, but this surely does seem to have a mechanical issue. It's not all electrical.

    Your 77A etc is NOT a "real" operating current.... that is a stalled motor...
  3. With the wye point not connected to neutral, the...

    With the wye point not connected to neutral, the total voltage is dependent n the voltage (and voltage drops) in all the windings, since the "virtual star point" is established by all working...
  4. It appears you are wanting to do almost exactly...

    It appears you are wanting to do almost exactly what this subforum is about. No problem asking here at all.

    For the benefit of folks who may not be familiar with UK power, please confirm that you...
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    715

    If it is a control wire, the chances of damage...

    If it is a control wire, the chances of damage are reasonably low. You'd have to trace the wire to see what it logically should connect to.

    "Pulsing" is a question. IF a vfd is overloaded, and...
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    715

    More info would increase the chances of an...

    More info would increase the chances of an intelligent reply.

    Machine? VFD? Pics if appropriate?

    Do you know what the wire comes from?

    I don;t want to be a pain, but when someone asks...
  7. Replies
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    3,447

    No clue what it is, but a key makes some sense,...

    No clue what it is, but a key makes some sense, as you would ideally like to see all of the pieces of a projectile exit the barrel together. Otherwise they probably would get separated before...
  8. Replies
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    1,308

    If both pulleys are crowned, the system will...

    If both pulleys are crowned, the system will accept a fair amount of misalignment and still work. That seems to work better with the rounded crown, vs the straight slope type, which is much easier...
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    Interesting.... I have here an old view camera,...

    Interesting.... I have here an old view camera, film about 4 x 5 or so, complete with several film cases. I've always wanted to try that camera out, but so far have not. It's been in the family...
  10. Thread: Horsepower..???

    by JST
    Replies
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    1,432

    I think you need a tie-breaker test. Try...

    I think you need a tie-breaker test.

    Try measuring from the underside of the bed way to the leadscrew at both ends. See what you get. You might also measure the side-to-side location as...
  11. Replies
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    I'd do that in a heartbeat. Only way to be sure...

    I'd do that in a heartbeat. Only way to be sure what is going on. OP may not have the variac, though. A doorbell transformer is probably pushing it, but, yeah.

    120V into the high voltage is...
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    Visible numbers do suggest that it will be OK. ...

    Visible numbers do suggest that it will be OK.

    One issue is that it is probably delta-wye. Depending on which way it is wye, it may be able to use wye, or have to be corner grounded.

    But...
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    I don't see that there is any problem with...

    I don't see that there is any problem with crowning both. The drive on my flat belt lathe is crowned on both and it tracks very well.

    It may be that you do not "have to" crown both, but that may...
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    1,203

    The worst it could do then is empty itself of...

    The worst it could do then is empty itself of oil. Seems like an idea, but one wonders what the folks did back when those things were common on machinery.
  15. Replies
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    1,159

    Well, then either the motor is not wound as one...

    Well, then either the motor is not wound as one would expect, or there is a short between windings.

    I could not read the motor plate in the pic, but it appeared to indicate 110/220.

    For...
  16. It's a little more interesting since the input...

    It's a little more interesting since the input draws at a 1.0 power factor. That "should" make it able to draw less real power than the possible output "apparent" power.

    But the actual answer...
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    No, shim stock around the central pivot to take...

    No, shim stock around the central pivot to take up the slop space so the scroll would not shift around. Basically a make-do, but it worked and I still use the chuck on occasion
  18. Replies
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    Continuity is not a surprise. it's normal. ...

    Continuity is not a surprise. it's normal.

    The switch is normally closed, and only opens when the motor is running.

    And, power from the wall has to get to all the windings. So one would...
  19. They are quoted at about 97% efficient, and that...

    They are quoted at about 97% efficient, and that should be correct, given that they are a switching type device. So not a power hog at all..

    Remember that they supply all the current through...
  20. Replies
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    1,159

    I would be fairly sure of just one capacitor. ...

    I would be fairly sure of just one capacitor. Not enough wires for two.

    For capacitor start motors, the capacitor (start) winding may be lower resistance than the main windings. But,...
  21. The problem with a lot of european contactors is...

    The problem with a lot of european contactors is that they are not made like American ones. We rate them for motor size in HP, and the rating has built-in allowance for inrush etc. That results...
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    Yes. The ones in the pics appear to have a...

    Yes. The ones in the pics appear to have a knurled cap, which would seem to suggest they are threaded. That in turn would probably allow felts of some type, either in the feed, or coming up...
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    The grooves are for oil distribution. It seems a...

    The grooves are for oil distribution. It seems a little odd that they are triangular, and come so close to the front thrust bearing edge, but otherwise they seem pretty normal.

    The triangular...
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    With just the one pic of the oiler, it's a little...

    With just the one pic of the oiler, it's a little hard to be sure, but I would expect that the oiler was supposed to have felt in it, which would retain the oil and somewhat meter it out. I'd have...
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    I would have been shocked if they DID have the...

    I would have been shocked if they DID have the data. Most companies don't have it anymore just through "attrition", and more recently companies have been actively destroying that old data because...
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