Shop OBEX P1 Docs P2 Docs Learn Events
12v Motor control with photo-resistor. Help — Parallax Forums

12v Motor control with photo-resistor. Help

ArchiverArchiver Posts: 46,084
edited 2003-02-11 04:32 in General Discussion
I am just starting to work with Basic stamps and want a photo-resistor to
control a 12v motor (Easy Roller). What do I need? An H-bridge? Just a
carrier board?
I have gotten a servo to work with the photo-resistor, but the 12v motor is
stumping me.
Any help would be great.

Thanks
Kevin

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2003-02-11 02:18
    Kevin,

    The servo thing works because the Stamp pin does not actually power the
    servo itself -- it only provides a control signal that tells the servo where
    to move to. A circuit inside the servo actually controls the servo motor.

    With a 12-volt motor, the Stamp pin is not capable of providing enough power
    to run the motor. You have to use some sort of external circuit to control
    the motor power. If you want to be able to make the motor go different
    speeds and change directions you do need an H-bridge. If you need a single
    speed and direction, its much easier.

    I didn't see anything in the StampWorks section on DC motors, so you may
    want to browse the Nuts & Volts articles on Parallax' web site and see what
    they have:

    http://www.parallax.com/html_pages/resources/nvcolumns/Nuts_Volts_Downloads.
    asp

    Original Message

    > I am just starting to work with Basic stamps and want a photo-resistor to
    > control a 12v motor (Easy Roller). What do I need? An H-bridge? Just a
    > carrier board?
    > I have gotten a servo to work with the photo-resistor, but the 12v motor
    is
    > stumping me.
  • ArchiverArchiver Posts: 46,084
    edited 2003-02-11 02:54
    Ok Now I understand Thanks !!!
    Just looked at the Nuts & Volts articles, but didn't see anything.

    Kevin
    -- In basicstamps@yahoogroups.com, Rodent <daweasel@s...> wrote:
    > Kevin,
    >
    > The servo thing works because the Stamp pin does not actually power the
    > servo itself -- it only provides a control signal that tells the servo where
    > to move to. A circuit inside the servo actually controls the servo motor.
    >
    > With a 12-volt motor, the Stamp pin is not capable of providing enough
    power
    > to run the motor. You have to use some sort of external circuit to control
    > the motor power. If you want to be able to make the motor go different
    > speeds and change directions you do need an H-bridge. If you need a
    single
    > speed and direction, its much easier.
    >
    > I didn't see anything in the StampWorks section on DC motors, so you may
    > want to browse the Nuts & Volts articles on Parallax' web site and see what
    > they have:
    >
    > http://www.parallax.com/html_pages/resources/nvcolumns/
    Nuts_Volts_Downloads.
    > asp
    >
    >
    >
    Original Message
    >
    > > I am just starting to work with Basic stamps and want a photo-resistor to
    > > control a 12v motor (Easy Roller). What do I need? An H-bridge? Just a
    > > carrier board?
    > > I have gotten a servo to work with the photo-resistor, but the 12v motor
    > is
    > > stumping me.
  • ArchiverArchiver Posts: 46,084
    edited 2003-02-11 04:32
    I think it may be in the Stamps in Class stuff, but I didn't see it on the
    site right away. I'll see if I can locate it later.
    Original Message

    > Just looked at the Nuts & Volts articles, but didn't see anything.

    > > The servo thing works because the Stamp pin does not actually power the
    > > servo itself -- it only provides a control signal that tells the servo
    where
    > > to move to. A circuit inside the servo actually controls the servo
    motor.
    > >
    > > With a 12-volt motor, the Stamp pin is not capable of providing enough
    > power
    > > to run the motor. You have to use some sort of external circuit to
    control
    > > the motor power. If you want to be able to make the motor go different
    > > speeds and change directions you do need an H-bridge. If you need a
    > single
    > > speed and direction, its much easier.
Sign In or Register to comment.