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  1. #40
    Join Date
    Aug 2000
    Location
    Austell, Ga.
    Posts
    1,294
    Billy, I apologize now for even entering "My" thoughts about the "Chicken & Egg" scenerio and any "Amplitude Modulation" accepted outlooks on something as simple as an open rotor bar. While simple in its being, the task of ascertaining the "Why & How Come" of the indications are far....Far more complex in thier nature. The "Harmonics" involved of the now mixed frequencies of an open rotor condition creates new forces that comes into play.
    Harmonics is, and will always be the mixing of two(or more) frequencies(fundemental) and getting an almost infinite number of new frequencies. That is the result of the fact that the new frequencies are created by the "Sum & Difference" of the original freq's..The new freq's are refered to as "First Harmonics"..Now...add(and subtract) those new frequencies to the original two frequencies and you have the "Second Harmonic"..Add & subtract "All" of those and you can see that you are getting into an infinite number of freq's. By the way...Didja' know that the destroying limitation of VSD's is the 7th & 13th harmonics of the output freq' combined with the switching frequency.
    With just a single open rotor bar we now have a great deal of frequencies and thereby polorizing forces acting upon the motor in question. My point to all this is it the newer magna-motive forces we see slowing the motor or a simple amplitude modulation force as the open rotor bar heals itself (somehow) and restores the rotor to its original condition on a rhythmic cycle...Pick one.....
    I ain't typed this much since my last resume.....
    Ain't "None" of us as smart as "All" of us..

  2. #41
    Join Date
    Aug 2009
    Location
    Prattville, Alabama
    Posts
    1,989
    Did you ever see the movie "Deliverence"? Where the guy in the boat playing dueling banjoes with the local guy couldn't keep up? That's the way I feel. "I'm lost, I can't keep up". Oh well, at least it's only my head that hurts...

  3. #42
    Join Date
    Feb 2004
    Location
    Georgia
    Posts
    354
    Quote Originally Posted by chillerguy81 View Post
    Does this chiller have an Optiview display? If so you can get the design info from the sales order screen.
    Look at first post pic...
    Superheat, that must be REALLY hot.

  4. #43
    Join Date
    Feb 2004
    Location
    Georgia
    Posts
    354
    Just a few questions, have you verified the accuracy of ALL the sensors/transducers? Sometimes things aren't always as they seem. What is the chilled water setpoint?
    Just curious, have you tried lowering the condenser inlet water temp if possible and observing any results?
    From your previous posts it sounds as though your are being very thorough and have a good handle on things
    Is the machine making setpoint? If not then why? What are the pressures doing when the amps are fluctuating? Surge would show up on a set of guages pretty well, whereas the micro might miss it. From your youtube video it almost seems too fast for a surge, but that is open to interpretation (sound would help).
    On diagnosing rotor bar problems, yeah that is not always an exact science, I have a machine that was absolutely guaranteed as having open rotor bars and that was about 30000 hours ago, still running and making capacity.

    That's all I have right now!
    Superheat, that must be REALLY hot.

  5. #44
    Join Date
    Aug 2009
    Location
    Taiwan
    Posts
    63
    Hi Turbomaster,
    The surge will make a really terrible noise, when the first time I started the chiller, the sound was more like a rotation stall owing to shortage of refrigerant charge, then I have charged totally 180Kgs refrigerant to the chiller, now I believe the chiller is running at normal condition except the current fluctuation,
    Tomorrow I am going to do the open rotor test by adopting a variable transformer, hopefully I can obtain some useful outcome,
    also why the chiller never makes the setpoint will be a focal point.
    Thanks for your valued suggestion.
    Please help on checking the attached pictures, is it the right stuff for checking the open rotor?
    Attached Images Attached Images

  6. #45
    Join Date
    Aug 2009
    Location
    Taiwan
    Posts
    63
    I also have contacted a local motor shop, they will come to job site to carry out an on-line analysis test for the motor.

  7. #46
    Join Date
    Aug 2000
    Location
    Austell, Ga.
    Posts
    1,294
    Taicool, Looks like you are ready as long as you also have an analog Clamp-on ammeter to monitor the applied current. On that size motor and using the full 130 volts output you should be very close to 10 amps to the motor.
    A current drop of 5-10% while rotating the rotor will confirm the "FACT" that it is an open rotor. However, If "No" deviation occurs, I would then hope that your motor shop can confirm or not the open rotor problem.
    "Please".....Keep us informed as to the outcome.
    Also..."Sneak-a-Peek" at the make/model of the test equipment the motor shop uses.
    Ain't "None" of us as smart as "All" of us..

  8. #47
    Join Date
    Sep 2007
    Location
    Somewhere in the world.
    Posts
    1,595
    Interesting thread guys found this pdf with info. on the prolem that everyone is talking about good reading.
    Attached Files Attached Files
    Arguing with your Boss is like wrestling with a pig in
    mud.
    After a while you realize that while you are getting
    dirty, the pig is actually enjoying it.

    It is not exactly cheating, I prefer to consider it
    creative problem solving.

    25 years ago we had Bob Hope , Steve Jobs , and Johnny Cash today we have no Hope no Jobs and no Cash !
    I can fix broke but i can't fix stupid !

  9. #48
    Join Date
    Aug 2000
    Location
    Austell, Ga.
    Posts
    1,294
    Great reading there York56.
    Now at least I understand why using any of my oscilloscopes looking at that noisy ass signal on the CT outputs meant absolutely "Nothing"..Without the propriatary programming stuffed in some fancy puter..
    Taicool, is this unit at the American Embassy in Bangkok???? I remember working on a couple of York R-114 HT's back in the 70-80's...
    Took me 3 weeks to replace the motor terminal O-rings on one chiller.
    (Liberty wuz' great!!!)
    Ain't "None" of us as smart as "All" of us..

  10. #49
    Join Date
    Aug 2009
    Location
    Taiwan
    Posts
    63
    No, the chiller is YK style C, and is installed at Mitsukoshi department store in southern Taiwan.
    When I just joined York twenty years ago, I had dealed with some HT chillers with R11, but I believe all the HT chillers are obsoleted now, the last one I worked on was about ten years ago.

  11. #50
    Join Date
    Sep 2007
    Location
    Somewhere in the world.
    Posts
    1,595
    Quote Originally Posted by chillerguy81 View Post
    Does this chiller have an Optiview display? If so you can get the design info from the sales order screen.
    chillerguy81 don't always put your trust in a optiview sales order screen because if that micro has been changed and the person who did the replacement didn't take all the info. down before it was replaced there is a good possibility that the info. is garbage anybody could put anything in that screen best is to get it from the source (ie) manufacture spec. just a little tid bit of info. for you that would be for any machine with a optiview.
    Arguing with your Boss is like wrestling with a pig in
    mud.
    After a while you realize that while you are getting
    dirty, the pig is actually enjoying it.

    It is not exactly cheating, I prefer to consider it
    creative problem solving.

    25 years ago we had Bob Hope , Steve Jobs , and Johnny Cash today we have no Hope no Jobs and no Cash !
    I can fix broke but i can't fix stupid !

  12. #51
    Join Date
    May 2008
    Location
    Central Pennsylvania
    Posts
    438
    Quote Originally Posted by york56 View Post
    chillerguy81 don't always put your trust in a optiview sales order screen because if that micro has been changed and the person who did the replacement didn't take all the info. down before it was replaced there is a good possibility that the info. is garbage anybody could put anything in that screen best is to get it from the source (ie) manufacture spec. just a little tid bit of info. for you that would be for any machine with a optiview.
    Good point and thanks for the info. This is a good thread, I must have missed the pic of the panel I guess!

  13. #52
    Join Date
    Jan 2004
    Location
    Atoka, TN
    Posts
    42
    Just a thought I had a 600 Ton Carrier with this same issue, fighting it for three weeks. Come to find out machine had a small mixture of R-22 in it, mixed with R134A. Traced records found a reclaim drum that had not been cleaned on a earlier repair. Caused machine to surge and drop out on Low Line Voltage, this safety just happened to be the one that picked the problem up.

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