high amperage draw on new motor

Discussion in 'General Electronics Chat' started by natox, Jul 8, 2013.

  1. natox

    Thread Starter New Member

    Jul 4, 2013
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    I have a 15 horsepower motor hooked up to 3 phase 480 and it's supposed to be drawing 16 to 17 amps it's drawing 29 and its overheating its controled by relays and goes through a contactor and is on a 30 amp breaker and I don't know what is causing it.do I need to put it on a VFD? Its for a blower in a car wash and it never had anything else before on the motor
     
  2. strantor

    AAC Fanatic!

    Oct 3, 2010
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    Is it a dual voltage motor? do you have it wired for 480V?
     
  3. tubeguy

    Well-Known Member

    Nov 3, 2012
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    Was this motor replaced because the existing motor failed?
     
  4. Duane P Wetick

    Active Member

    Apr 23, 2009
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    I'm almost certain that you have it wired for low voltage when it should be wired for high voltage...Re-do the connections at once for High Voltage! You may have a dual voltage starter, ie: Low Voltage Start...High Voltage Run.

    Cheers, DPW [Everything has limitations...and I hate limitations.]
     
  5. strantor

    AAC Fanatic!

    Oct 3, 2010
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    Me too, but I have the uncanny power of changing root cause by expressing absolute certainty. So I don't.
     
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  6. natox

    Thread Starter New Member

    Jul 4, 2013
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    it is dual voltage 208 & 460 its got 12 different leads for different combinations of hookups for delta run or delta start wye start to Delta run. I'm a state certified journeymen electrician an inside wireman with the International Brotherhood of Electrical Workers I'm confident in my abilities to know that its hooked up correctly(not said in athe one who replaced was doing the exact same thing and tripping the breaker
     
  7. gerty

    AAC Fanatic!

    Aug 30, 2007
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    Have you tried running it unloaded?
     
  8. Dodgydave

    Distinguished Member

    Jun 22, 2012
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    Ok lets have the pictures of it then and a model number..
     
  9. natox

    Thread Starter New Member

    Jul 4, 2013
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    Havent tried to run it unloaded but its only a mechanical blower and I can spin it with my hand but I will take pictures soon as I get back to that site thank you all for your help
     
  10. crutschow

    Expert

    Mar 14, 2008
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    Perhaps you somehow lost a phase. Have you checked the current in all three phases?
     
  11. GetDeviceInfo

    Senior Member

    Jun 7, 2009
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    So, how is the motor started, across the line?
     
  12. BillB3857

    Senior Member

    Feb 28, 2009
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    Have any shrounds, etc. been removed from the blower and not replaced. An increase in the intake size of a blower can cause higher loads on the motor. Listen to the motor on a vacuum cleaner when you restrict the air flow. Motor unloads and speeds up.
     
  13. natox

    Thread Starter New Member

    Jul 4, 2013
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    no shrouds have been removed from it the old motor was doing the exact same thing figured and decided to replace it
     
  14. gerty

    AAC Fanatic!

    Aug 30, 2007
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  15. shortbus

    AAC Fanatic!

    Sep 30, 2009
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    gerty likes this.
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