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  1. YorkMech1

    Motor-test without rotor

    Thank you jraef for that information..For over 40 years this has bothered me. While I seldom ever post on this site, I do however read each & every post here with interest.
  2. YorkMech1

    Motor-test without rotor

    Starkopete; When you run your next ball-bearing/false rotor test on a stator, could you please explain to this lowly scribe why in the world the ball bearing goes in the "Opposite" direction of the false rotor. While the false rotor will always give the true rotation of an installed rotor, the...
  3. YorkMech1

    spherical ball roation under roatating magnetic field

    Now I gotta' crayfish on this one...I just got through playing with the Ball Bearings again... While it is true that the ball is whizzing around inside the stator "Opposite" the direction of the true rotor, The Ball "Itself" is rotating in the same direction that the rotor will. Since the ball...
  4. YorkMech1

    spherical ball roation under roatating magnetic field

    SteveKW (Electrical) Jun 27, 2004 The ball runs around the stator sounding like a car following the rails and hitting every railroad tie. I never paid attention, but I would assume it would go in the direction of rotation. Just a lot slower because of the slip. Nope...Sorry Steve... The Ball...
  5. YorkMech1

    motor stopping rapidly during a fault

    I normally just read and absorb as much wisdom from the learned ones that post here as I can. In this case, since it involves a piece of equipment I am more than fairly familar with, I feel compelled to ask the following as well as interject some thoughts. 1- It seems to me that someone failed...
  6. YorkMech1

    MEGGER

    The term "Megger" is a Registered trademark in 32 countries of various Insulation Testors Mr. Biddle & Company produce... I know several of the Inspectors from Hartford that will accept "Only" the readings from a "Megger".. (James Biddle & Compny)
  7. YorkMech1

    Trane CVHE

    Richard; Well now.....From one Richard to another, Hey!!..we gotta' stick together.......O.K...How about a fax# or something, the manual's about 80 pages or so... I hope it's a 1-800 fax #...or I'm afraid you might be outa' luck... If you have been in any of the CV's, or PCV's, then this puppy...
  8. YorkMech1

    Expansion Tank Air charge Pressure

    Regularly when selecting an expansion tank for hot water (bladder type), what kind of air fill pressure should be? The "Standard" pressure, or the ones most used & sometimes "Fine-Tuned" in the field is "12PSIG" on an empty expansion tank. Without the coveted...
  9. YorkMech1

    Raising the chilled water temperatures to save energy !

    JimD1 has put up the stumbling block of any idea of saving money by raising the lvg. water a couple of degrees...The space humidity jumps by several points as the dehumidification capbility of the chill water coil is compromised... If its a process cooler, noooooo' problem, as long as the...
  10. YorkMech1

    Chilled Water vs. DX

    Greybeard; I fear your plant HVAC guys might have led you astray on the numbers.. "ALL" hospitals (example)"MUST" use 100% fresh(outside) air for the operating, recovery & delivery rooms. Many of these use "D/X" units and are set-up to supply 55deg/f (52preferred)&...
  11. YorkMech1

    Different Directions of "False" Rotors.

    motorman; Interesting about the bucket getting picked up by a stator...Thats sounds a little scary...I also noticed that the lil' "Ball-Bearing" Test I mentioned, never gets the Steel Ball "Anywhere" near the Syncronous-speed. Also the ball slows to a crawl as the voltage...
  12. YorkMech1

    Different Directions of "False" Rotors.

    electricpete; Sorry for not being specific on the ball bearing. I was referring to a "Ball" from an old bearing of 1/2" to 3/4" in diameter...larger balls tend to become "Mindless-Missiles" when you turn off the power..Fairly safe as long as power is maintained and...
  13. YorkMech1

    Different Directions of "False" Rotors.

    Many times "Only" the stator of certain motors, up to 2500HP, for rewinding. Since the proper rotation of the rotor is critical and must be determined before re-assembly, I test the rotating field with a false rotor I carry from a very small fractional HP motor, mounted inside a short...
  14. YorkMech1

    Inertia Constant

    electripete; Sorry for the confusion, I was responding to the "Units" as posted. I could be outdated, but using the latest tables I can find, I see that by "SI" postings that; J= Joules I,J= kg^m2 (Moment of Inertia) H= Henrys
  15. YorkMech1

    Inertia Constant

    Both equations appear are for Units of Energy or Work. It appears improper use of Upper/Lower case was used in the second equation. J= GD(squared)/H J= Joules,(SI unit of Energy) G= Gauss, (GCS unit of flux Density) H= Henry, (SI unit of Inductance) kW sec/kVA k= (Lower Case) (SI prefix for...
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