Help identification of switch type

Discussion in 'General Electronics Chat' started by Rigemortis, Feb 27, 2019.

  1. Rigemortis

    Thread Starter New Member

    Feb 27, 2019
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    I work on a Litton glass blowing lathe. The motor at work has a forward stop reverse switch. This switch when moved from "forward" direction to the center (off) the switch stops you from moving it to the other direction till you release the pressure. Once you release the pressure from your hand you can move the toggle to the other selection. This provides the motor a brief time to stop rotation before changing directions.

    I want to buy a switch like this for my lathe at home to use to reverse the polarity of my dc motor. I was told it was called a " forward brake reverse switch" I have found some online but they do not indicate it has this type of motion locking toggle. It interests me to make sure I get this type so I don't slam my motor in reverse before it stops motion. It is convienient that the toggle stops me from over flipping the double throw in a glass blowing moment of intensity.

    What is a switch called that has this type of center lock?

    I found online one that has a braking resistor...what is that? (By kbmd labeled forward brake reverse)

    And another on Grainger that just looks like a dpdt prewired for polarity. (Labeled forward stop reverse)

    My motor looks like a 115v dc with only a red and black wire.

    The controller is a Dayton 4z527h

    Also...the controller's on off switch is wired to and from the circutry board so I can imagine reversing the polarity there could be distructive so I'll have to wire the forward stop/brake reverse into the DC out wires.

    Lastly...what is the difference in the naming vs functionality when it comes to "brake" and "stop" when labeling a switch?

    Thank you in advance.
     
  2. pmd34

    Active Member

    Feb 22, 2014
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    153
    Hi Rigemortis, can you supply a few photos with your post so we can get a better idea of what the switch looks like?
     
  3. Yaakov

    Well-Known Member

    Jan 27, 2019
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    Pending photos of your home lathe’s PCB (Printed Circuit Board)—the front and back with traces visible and part numbers readable would be most helpful, but the best view you can get is better than nothing—I can answer this part.

    When you disconnect power from the motor, momentum will keep it rotating. A motor under power rotates, conversely, rotating a motor produces electric power. Without a load, the motor doesn’t notice this, but when connected to something to power, the electric load equates to a mechanical load and is like friction. The motor has to do work to provide the current to the load. So, a braking resistor is one connected to the unpowered by spinning motor to provide something akin to a mechanical brake, applying what appears to be friction by forcing the motor to work to power it.

    It muse be properly rated for the application to avoid damage to the resistor or motor.
     
  4. Rigemortis

    Thread Starter New Member

    Feb 27, 2019
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    0
    I will try for the circutry board in my controller Monday....

    Pic 1: work controller
    Pic 2: home controller
    Pic 3: home controller spec plate
    Pic 4: home motor spec plate
     
  5. pmd34

    Active Member

    Feb 22, 2014
    361
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    It looks like a "lever toggle switch" but the locking mechanism you mention is unfamiliar to me. You can get locking versions but they tend to have a sliding sleeve on the arm which locks into an indentation on the switch body preventing it from moving.
     
  6. Yaakov

    Well-Known Member

    Jan 27, 2019
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    pmd34 likes this.
  7. MaxHeadRoom

    Expert

    Jul 18, 2013
    18,415
    5,654
    It is commonly used by KB DC controllers, usually any Baldor or KB DC motor control supplier can supply one.
    Many of the KB's also use a braking resistor.
    Does your lathe have a DC motor? As this is usually what it is used on.
    Max.
     
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