AC motor reversing

Discussion in 'General Electronics Chat' started by tamarack, Feb 22, 2011.

  1. tamarack

    Thread Starter New Member

    Feb 22, 2011
    Hi Guys
    I have a problem that has been driving me crazy. I have a new 1hp 115/230v capacitor start, induction motor I wish to start/stop & reverse using a magnetic 2coil reversing relay/contactor.
    I understand how the motor works and how to energize the coils on the contactor. My problem is wiring the 220v lines to the 6 lines of the motor via the contactor.
    I can do it if I use 115v and a 3PDT reversing contactor, but for the life of me I can't figure out(or even find a diagram online) that shows how to do it using 220v. After a million tries(on paper) I don't think I can do it with my existing 3 pole contactor. I'm pretty sure I need a 4PDT reversing contactor.
    Does anyone know the minimum number of poles I need and where I can get a simple wiring diagram.
    To turn the motor, one 220v leg is connected to T1, then T2,3 and 6 are wire nutted. The other 220v leg is connected to T4 and T5.
    To operate in reverse the T6 and T5 are intrerchanged. This is a very common arrangement and I'm sure done a million times every day...but I can't....can you help?
  2. debe

    Well-Known Member

    Sep 21, 2010
    This is how i wired up a simmilar motor for a lathe using a 3pole 3position switch.
  3. tamarack

    Thread Starter New Member

    Feb 22, 2011
    Hi Daryl
    Thanks for responding but I think your power distribution system in Australia is different than ours here in North America, in that one leg of your 220v is +220v and the other is neutral. This gives you a different potential of 220v.
    Here we get it by one leg being +110v and the other -110v, the difference in potential being the 220v....there is no neutral. If a neutral(earth potential) is run we get 110v between it and either leg, which is our general household voltage for our smaller appliances.
    I learned this while in Australia a couple of years ago. Loved it there but the charger for my electronic stuff didn't work without a transformer.
  4. tamarack

    Thread Starter New Member

    Feb 22, 2011
    After much hair pulling, I got it figured out.
    Can't do It with 3PDT(center off) relay/switch. In order to disconnect all the motor leads to the power a 4PDT relay is required.
    I plan on using my old 3PDT relay and buy another SPST(for L1) and switch it on when either of the other 2 coils are energized.
    If anyone else needs this information, I would be glad to share the wiring diagram.
  5. debjit625

    Well-Known Member

    Apr 17, 2010
    Post it here,so that if anybody in future have this kind of problem he/she could get help from your post.
  6. Commander#1

    New Member

    Jan 22, 2011
    Hi Tamarack -
    I think it can be done. You say you have a 3PDT (center off) contactor. O.K. - kick this around a little bit. Your 220Vac
    HOT lead comes into Pole #1's common, T1 attaches to either of the P1 NO contacts with a jumper to the other P1 NO
    contact - this way, the HOT lead is connected to T1 during both FWD/REV; T2,3 are connected to P2's common with
    T5 connected to one of P2's NO contacts; your 220Vac Neutral and T4 are connected to P3's common with T6
    connected to P3's NO contact on the same side as T5; a cross jumper is connected from T6 to P2's unused NO
    contact; and a jumper is connected from T5 to P3's unused NO contact. In case the switch is backwards in operating
    the motor, just switch T5 and T6. I hope this is of some help.

    Phil Potter. :):)
  7. tamarack

    Thread Starter New Member

    Feb 22, 2011
    Thanks Phil
    That is the best I could do with the 3PDT contactor also. The problem I saw with that is connecting one leg of the 220v to the T4.
    This arrangement would mean that the T4 would always be carrying 110v, even in the C.O. position. Not knowing a great deal about the guts of a motor, I don't know if this would be a problem.
    Don't forget that, here in Canada, when we talk about 220v, there is really no neutral(except for the bare ground). Take a look at the reply I sent to Daryl regarding Australia's power distribution compared to Canada's.
    Your wiring is how I did the 110v motor with the same contactor. I'm pretty sure I need another set of contacts just to disconnect one leg in the "off" position.(the L,T1 connection)
    If I have missunderstood your explanation and I'm "out to lunch with my thinking":rolleyes: could you send a diagram.
    I will try to get a diagram of my arrangement on here also.
  8. tamarack

    Thread Starter New Member

    Feb 22, 2011
    I'm attaching this wiring diagram to expain how I am controlling the fine!
    If you have a simpler way to do it, I'd appreciate a diagram.
  9. BillB3857

    Senior Member

    Feb 28, 2009
  10. tamarack

    Thread Starter New Member

    Feb 22, 2011
    Hi Bill
    I sure would like to know how it could be wired to control a 220v single phase motor. I see from the catalogue page that the above switch is only one of a "series" that includes 1 to 4 poles and they suggest they be used for d.c., 110v and 220v motors. I know for sure a DPDT(with jumpers) switch is used for d.c. motors and 3PDT is needed for 110v motors.(all "center off"). The built in hesitation is to allow the motor to come to a stop so it can be reversed. I'm wondering if they mean that the 4PDT is designed for 220v single phase motors???
    I do have it working just fine but I sure would like a definitive answer as to it's control to see if I'm doing it the easiest way.
    I will try calling that company tomorrow(Eaton Control) and try to talk to a technical representative. I really have a hard time getting a company to answer an email. I'll let you know if I get an answer from them.
    Thanks Bill
  11. Reloadron

    Active Member

    Jan 15, 2015
    It looks like you have a Baldor Model VEL11304 .5HP, 1725RPM, 1PH, 60HZ, 56C, 3424LC, OPEN, F1 motor. Have you looked at the data sheet?

    The last page of the data sheeet linked to shows the connection options for 115 / 230 VAC operation and Rotation Direction.