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How can i use 5V to switch 24V on/off?

  1. Dec 19, 2011 #1
    I'm working on a project that uses a joystick to control a motor. The motor has an electric motor brake built in, and I want to be able to engage/disengage the brake with a button on my joystick.

    The motor runs on 24VDC, and the joystick runs on 5VDC. I currently have the button on the joystick configured as a dead man's switch for the motor (button has to be pressed to move the motor), and I would like to have the same button disengage the motor brake.

    I'm not real familiar with relays or other electronic equipment. Is there a device that I can wire the 5V button to as input, and have 24V as output to the motor brake?

    Thanks in advance for any suggestion/info.
  2. jcsd
  3. Dec 19, 2011 #2

    Simon Bridge

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    Yes: it's called a relay.
    Looks like you are about to become familiar then.

    Go to an electrical suppliers and say "I want a relay to switch 24V from 5V".
    They'll ask if you want normally open or normally closed (I guess you want open).
    They'll give you one.

    How did you rig the dead-mans-switch?
    Sounds like you have a single-pole button and you want it to do two tasks.
  4. Dec 20, 2011 #3
    Thanks for the info. I'll see what I can find in 5V to 24V relays.

    The push-button is wired into the motor controller as a digital input. The motor controller's software allows me to configure the digital input as a dead-man's switch. Your correct saying I want the single-pole button to have 2 functions. The motor brake is engaged when the motor is not moving to prevent back-driving. Pushing the button releases the motor brake and allows the motor to move. This will prevent someone from trying to move the motor while the brake is engaged which would push a lot of current to the brake or apply a lot of torque and possibly cause it to fail.

    Again, thanks for the info.
  5. Dec 26, 2011 #4
    I don't really understand your project. But I think you want to drive 24V from 5VDC. It's not difficult. You only need one 5V relay to control 24 motor. If you will, I can show you how to wire the circuit. It's not difficult. Take it easy.
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