Snubber for AC Motor

Discussion in 'The Projects Forum' started by Mopar_Mudder, Nov 17, 2015.

  1. Mopar_Mudder

    Thread Starter Member

    Mar 13, 2012
    43
    0
    I have a reversible AC motor that is activated by a 5v DC trigger using 3 relays. Problem is I am getting some sort or "noise" that is effecting the circuit that is triggering the relays. From my reading it seems maybe I need some sort of snubber on the motor. Problem is that I am not really sure how to do it or what to use.

    This is the motor http://www.grainger.com/product/DAYTON-Gearmotor-4Z062?searchQuery=4Z062A

    These are the relays: http://www.digikey.com/product-search/en?vendor=0&keywords=V23105A5301A201

    I attached a Schematic of what I have and picture also.

    [​IMG]

    [​IMG]

    [​IMG]
     
  2. MaxHeadRoom

    Expert

    Jul 18, 2013
    10,526
    2,369
    What size is the motor? Inductive with Capacitor?
    A R/C snubber is needed.
    The values will depend on the motor power.
    Max.
     
  3. Mopar_Mudder

    Thread Starter Member

    Mar 13, 2012
    43
    0
    Motor Technical Specs
    • Item AC Gearmotor
    • Voltage 115
    • Phase 1
    • Hz 50/60
    • Input HP 1/60
    • Gear Ratio 109:1
    • Full Load Amps 0.38
    • Insulation Class B
    • Enclosure TENV
    • Rotation Reversible
    • Motor Type PSC
    • Capacitor Required 2MDV4
    Item Motor Run Capacitor
    • Overall Shape Oval
    • Microfarad Rating 5
    • Voltage 370VAC
    • Hz 60/50
    • Shape Oval
     
  4. MaxHeadRoom

    Expert

    Jul 18, 2013
    10,526
    2,369
    Do you have a BEMF diode across each coil?
    Have you a diagram in schematic format rather than physical layout?
    Max.
     
  5. Mopar_Mudder

    Thread Starter Member

    Mar 13, 2012
    43
    0
    No I don't have a diode across the coils. It is really bare bones but served the purpose I needed to until I decided to add electronic controls to it.
     
  6. MaxHeadRoom

    Expert

    Jul 18, 2013
    10,526
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    Maybe you need to address that first?
    A couple of ¢'s.
    Max.
     
  7. Mopar_Mudder

    Thread Starter Member

    Mar 13, 2012
    43
    0
    Being I run current both ways through the coil of the relay right now am I going to have to use a diode bridge to make it all work?
     
  8. MaxHeadRoom

    Expert

    Jul 18, 2013
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    What is the purpose of that?
    Max.
     
  9. Mopar_Mudder

    Thread Starter Member

    Mar 13, 2012
    43
    0
    It is used to reverse the motor direction. One relay is always triggered regardless of input polarity, this one powers the motor no mater what. The other relay is only active when the input polarity is reversed, that relay is to reverse the motor direction.
     
  10. Mopar_Mudder

    Thread Starter Member

    Mar 13, 2012
    43
    0
    I just had a thought on this, and the relays can not be my problem. Reason is that I am running the motor with the manual buttons when I am testing this. When using those buttons none of the relays are tripped, just the switch button is pushed. So I don't think diodes on the relays will help if my thinking is correct.
     
  11. MaxHeadRoom

    Expert

    Jul 18, 2013
    10,526
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    You could try the RC snubbers across the AC close to the motors.
    Max.
     
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