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Type: Posts; User: johansen

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  1. Replies
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    i've used 7" wire wheels rated for 4500 rpm on my...

    i've used 7" wire wheels rated for 4500 rpm on my 4.5" angle grinder. the air drag loads it down and its a bit scary to use but, they hold up just fine.

    no way would i put a 14" wheel on a 9"...
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    motors buzz because the core is saturated and the...

    motors buzz because the core is saturated and the magnetic field is escaping the stator core and causing the rest of the motor casing to vibrate.. typically sheet metal.
  3. grind the circlip groove with one of those dirt...

    grind the circlip groove with one of those dirt cheap .040" thick 100mm angle grinder cut off blades for angle grinders. the groove will be mostly circular profile at the root of it which should not...
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    remove some of the run capacitors until you see...

    remove some of the run capacitors until you see that 250 volt number drop a bit, or just ignore it. 250 volts no load is not too high.

    you can then take those capacitors which were removed and...
  5. cavitation is also influenced by the gas pulled...

    cavitation is also influenced by the gas pulled out of the fluid on the suction side of the pump. if the gas does not get pushed downstream it flows around the impeller through the seals. or lack of...
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    the motor you have is probably repairable if you...

    the motor you have is probably repairable if you are willing to carefully examine the copper connection between the commutator and the coils. i'm suspecting fatigue failure.

    i repaired the motor...
  7. either you are single phasing the motor or you...

    either you are single phasing the motor or you have a volts per hz curve that is wildly incorrect.

    i can think of no reason why you would see more than nameplate full load amps for your lathe, as...
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    Did you add delta caps after the load reactor?

    Did you add delta caps after the load reactor?
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    Its not kosher but you can flush the air out of...

    Its not kosher but you can flush the air out of the lineset and indoor minisplit unit with the refridgerant. The instructions on how to do it are printed in the hieroglyphic instruction manual. No...
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    you could use a 9 wire motor as a 3 phase line...

    you could use a 9 wire motor as a 3 phase line reactor. lock the rotor so it doesn't spin up. the y connected coils would be disconnected and the other 3 coils used.

    the impedance will be on the...
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    the pure sine wave filter should be a special...

    the pure sine wave filter should be a special core that has a very high common mode inductance to filter out the common mode voltage, which is what destroys motor bearings.
    for example: Sine Wave...
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    Had some corespondance with a man who tried a...

    Had some corespondance with a man who tried a cheap automation direct line load reactor for the sine wave filter applications i have spoke of, and while it worked it got very hot. He found the...
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    I got away with as little as 500uH for a 400watt...

    I got away with as little as 500uH for a 400watt 240v vfd. (A 9mh 3 phase line load reactor had only 480uH common mode inductance)


    I found that 65 feet of 12/3 wire coiled up as tightly as i...
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    That filter seems suspicious to me. It is...

    That filter seems suspicious to me. It is probably a CLC configuration for noise removal.

    Go to home desperate and buy 3, 500 foot spools of 12 guage wire and you've got 3 inductors. Any ordinary...
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    I explained in my post on the other thread before...

    I explained in my post on the other thread before i saw this one.
  16. You probably need to pull the end plate off (its...

    You probably need to pull the end plate off (its staked in 3 places) to braze the ring together.

    The keys have a spring wrapped around them and once some rpm is reached they fly outward and touch...
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    Cheapest method will be a 480v vfd with a line...

    Cheapest method will be a 480v vfd with a line load filter on the output and delta connected capacitors to clean up the waveform. Collectively all 3 phases will still have a square wave of 340volts...
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    Regarding a 5hp motor with 2/3rds of its windings...

    Regarding a 5hp motor with 2/3rds of its windings passing 75% rated current, suppose it is running at no load, and consuming 200 watts.

    Then at full load it will dissipate 538 watts of copper...
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    as i'm aging i'm losing the mental capacity to...

    as i'm aging i'm losing the mental capacity to understand these kinds of schematics and motor diagrams.

    basically you've got a thermal protector with 1 input and 2 outputs.

    both outputs are...
  20. sorry for the double post but i wanted to get...

    sorry for the double post but i wanted to get your attention.

    it looks to me like the steel spring broke a long time ago and the arcing and pitting of those keys is because they are prematurely...
  21. If you have lost some of the keys, space them out...

    If you have lost some of the keys, space them out with copper or brass washers. Clean them up get rid of the burrs.

    They make contact with the commutator (once centrifugal force kickes in which...
  22. I have one. From a spa pump motor. 2hp at 3600...

    I have one. From a spa pump motor. 2hp at 3600 rpm and either .5 or .25hp at 1750. Capacitor run for 1750 rpm and resistance start through a clutch switch for 3600 rpm. 12 amps at 230v or 4.4 amps at...
  23. well you got to admit though that bleed resistors...

    well you got to admit though that bleed resistors would be effective in hiding the information needed to diagnose the fault in the first place.. which sounds like an intermittent connection.
  24. but no way could you get the starting current...

    but no way could you get the starting current down to just 1.8 times the full load running amps, while providing 112% full load starting torque.. which sounds like that torque is flat all the way up...
  25. Thermite you could at least try to explaine why...

    Thermite you could at least try to explaine why they are needed in the event of a disconnected capacitor with a stored voltage of as high as say + or - 240*1.41 voltsdc, when that capacitor is...
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