Page 2 of 2 FirstFirst 12
Results 11 to 17 of 17

Thread: motor troubleshooting question.

  1. #11
    Join Date
    Feb 2016
    Location
    Illinois
    Posts
    488
    Quote Originally Posted by drcampbell View Post
    Is the motor actually designed/rated/labeled for 208 volts? A 230-volt motor on a 208-volt circuit might be hard to start.
    Very good point. I spent a good part of my career in the compressor business and don't recall ever seeing a 208 V single phase motor. The company I work for never offered such a beast.

  2. #12
    Join Date
    Dec 2007
    Location
    NE Nebraska
    Posts
    33,534
    Quote Originally Posted by drcampbell View Post
    Is the motor actually designed/rated/labeled for 208 volts? A 230-volt motor on a 208-volt circuit might be hard to start.
    Unless the 208 volts runs at the low end of what is acceptable, it probably works fine. Here 208 volt systems almost always start out unloaded near 215 volts. 207 volts is -10% of motor rating of 230.

  3. #13
    Join Date
    Dec 2007
    Location
    NE Nebraska
    Posts
    33,534
    Quote Originally Posted by Fulthrotl View Post
    yeps. i'll log voltage and current at the contactor.... i was looking
    at the current when starting, and instead of a spike and drop off,
    it kept fluttering between 50 and 110 or so amps, until it hit synchronous
    speed.
    If there is a contactor, make sure it is not "chattering" when current is high - like you would have during starting. If so - you may have too much voltage drop during starting and it is dropping the contactor out, then it pulls back in when current stops because voltage went back up, repeat cycle. If it is lucky enough to accelerate the motor this goes away once current reaches a certain level.

    If this always worked before, something has changed.

  4. #14
    Join Date
    Feb 2009
    Location
    Durango, CO, 10 h 20 min without traffic from winged horses.
    Posts
    8,773
    I agree with others that the unloader is always worth checking when it comes to compressors. Another possibility is that there is a blown starting cap and the motor is starting off the running cap.
    Once in a while you get shown the light
    In the strangest of places if you look at it right. Robert Hunter

  5. #15
    Join Date
    Apr 2005
    Location
    Atlanta,GA
    Posts
    5,500
    Quote Originally Posted by Tony S View Post
    The centrifugal switch you can only check by stripping the motor end bell.

    This is what I found inside a S Ph motor

    That looks nasty. Years ago I worked for a compay that manufactued some of their own printed circuit boards and all that fiberglass dust would get inside of the motors.

    A friend of mine worked for a chicken processing plant and would tell horror stories about what they would find in motors.
    The 95% of people that you can't trust give the other 5% a bad name.

  6. #16
    Join Date
    Dec 2007
    Location
    NE Nebraska
    Posts
    33,534
    Quote Originally Posted by growler View Post
    That looks nasty. Years ago I worked for a compay that manufactued some of their own printed circuit boards and all that fiberglass dust would get inside of the motors.

    A friend of mine worked for a chicken processing plant and would tell horror stories about what they would find in motors.
    I thought it looked relatively clean compared to some I have seen

  7. #17
    Join Date
    Mar 2016
    Location
    The Motor City, Michigan USA
    Posts
    502
    Quote Originally Posted by growler View Post
    That looks nasty. ... fiberglass dust ... chicken processing plant
    That why they make totally-enclosed fan-cooled motors and washdown-duty motors.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •