How to reverse an electric motor with a switch

Discussion in 'General Electronics Chat' started by lambtim, Mar 8, 2015.

  1. lambtim

    Thread Starter New Member

    Mar 8, 2015
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    Hello, I know little to nothing about electric motors but want to connect one of the electric motors I have to a switch so I can make it go forward and backwards. The idea is to have the motor run a cable looped on pullies with a flag attached in the middle. I need the flag to move forward and backwards to train a horse. I have several electric motors that were left on my property when I purchased but like I said, I know almost nothing about them. I have attached pictures of two motors but have others too.
     
  2. Reloadron

    Active Member

    Jan 15, 2015
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    The Westinghouse is a 3 phase motor and unless you have 3 phase power forget about using it. Both motors have fast RPM. While the first motor is a single phase general purpose AC motor it would not be easy to reverse using a switch. For what you plan to do among the best motors are DC Gear Head motors which can get you low RPM (Speed) and can generally be easily reversed. Some garage door motors are easily reversed AC motors and geared down. Before we can suggest a circuit or switch combination you need to find a good reversible motor that will work for your application.

    Ron
     
  3. MaxHeadRoom

    Expert

    Jul 18, 2013
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    You could use the 3ph motor with a VFD and 230v 1ph supply, you would also have a simple way of reversing by means of a couple of limit switches for the inputs to the VFD with no relays.
    Max.
     
  4. debe

    Well-Known Member

    Sep 21, 2010
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  5. debe

    Well-Known Member

    Sep 21, 2010
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    This is how you wire a single phase motor for reversing, had to wire one up for a lathe.
     
  6. KLillie

    Member

    May 31, 2014
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    I agree that this might be a pain. You would be better off with DC motor for this idea.
     
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  7. lambtim

    Thread Starter New Member

    Mar 8, 2015
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    Please excuse my ignorance but what is a VFD?
     
  8. MaxHeadRoom

    Expert

    Jul 18, 2013
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    A VFD or Variable Frequency Drive is a way of controlling the rpm of a 3ph motor, the second pic in your OP.
    It also allows running a 3ph motor on domestic/residential supply from single phase, the VFD produces 3ph out and can be controlled either by the built-in keypad, or by a low level input remote switches etc.
    Do you intend the FWD/REV to be manual or automatic?
    Max.
     
  9. Dodgydave

    Distinguished Member

    Jun 22, 2012
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    The first motor looks like a dual speed, and maybe a capacitor run type,,,,
    If you have a 3phase supply and a 3phase motor, you can reverse any two phases to make it go into reverse. Post photos of all the motors you have,

    if you on have a single phase at your premises with 3phase motors, you need a variable frequency motor drive
     
    Last edited: Mar 9, 2015
  10. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    Forget those motors as a VFD = $$$
    And unless your "flag" is very heavy its massive..massive overkill using that motor..
    Great to have motors lying around but in this case its more work/money to use them than to just buy different stuff..

    Just get a cheap DC motor (geared with an RPM you want) and appropriate power supply.
    Then a simple double pole switch to swap polarity like this
    [​IMG]
     
  11. MaxHeadRoom

    Expert

    Jul 18, 2013
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    DC motor and controller compared approx = ~ $160.00 VFD from Automation Direct?
    Max.
     
  12. Nykolas

    Member

    Aug 27, 2013
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    Danger: I am repeating myself (yet again)! A motor needs to come to a full stop before being reversed. Otherwise damage to the armature will shortene lifespan. Use a 3-poisition "hesitation" switch to do that. E
     
  13. MaxHeadRoom

    Expert

    Jul 18, 2013
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    This is handled automatically in a VFD;)

    But what about the common method of plugging a (3ph) motor?:rolleyes:
    Max.
     
  14. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    For this project I'd suspect a DC motor could be easily $20.00 or less..

    Just seems silly to utilize a 3ph motor/vfd to pull a small flag back/forth..
    Heck just one direction "might" be all that may be needed.. Just have the flag ride right around the pulley at each end and it would go back and forth all day without ever needing to reverse.. but I don't know the specifics of the requirement.
     
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  15. ian field

    Distinguished Member

    Oct 27, 2012
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    If you're running a 3-ph motor from 3-ph supply - reversing is as simple as swapping 2 of the phases over.

    That can be done with a DPDT.
     
  16. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    The owner didn't even want to take those motors to the scrap yard. I wouldn't count on them working once you get them all wired up.

    I would get a garage door opener or something already with a pulley and stop switches / reverse capabilities. Just add a longer belt or chain or cable and then you have a push-button to control the whole thing too. Good luck.

    By the way, I've never heard of training a horse with a moving flag. What are you doing? What is the horse getting trained to do?
     
  17. MaxHeadRoom

    Expert

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    They need the leaves blowing out at least!:p
    Max.
     
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  18. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    I always love that campfire smell when I start my old motors from the horse barn.
     
  19. lambtim

    Thread Starter New Member

    Mar 8, 2015
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    Thanks for all of the input. I believe a garage door opener will be the best option for me since it comes with a remote and is already set to move in both directions. To answer the question about how it will be used- I am teaching a horse to follow a cow/calf/moving flag. The horse will learn to stop when the flag stops and reverse directions if needed similar to a live animal. The remote helps so I can control the flag while riding the horse and will not need someone to operate a switch. The entire setup is sold online for around $1000.00 to $1200.00 so I'm sure I can build it cheaper using a garage door opener.
     
  20. Reloadron

    Active Member

    Jan 15, 2015
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    Yeah, which is why I said for that specific motor unless you have a 3 phase supply forget about it. You can also run a 3 phase motor from single phase by adding a cap (not the best way to go). Finally you can find a single phase VFD that will create 3 phase. So unless you have 3 phase power to begin with you need to create it which is why I said forget about it. Finding a single phase reversible or DC type motor is likely easier.

    Anyway, all this poster wants to do is run a flag around to train horses so I see him needing a slower speed, similar to the small reversible motors at my indoor range for running targets out and back. A small fractional HP motor with a gear head is all that is needed. I like the garage door motor approach. Could likely also hack a vari-speed reversible mains powered electric drill. Not like you need much torque for this application.

    Ron
     
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