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.
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...
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...
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...
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...
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)
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...
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...
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...
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)&...
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...
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...
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...
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
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...
