Adding Multiple Motors to a Circuit

Discussion in 'The Projects Forum' started by person_man, Oct 2, 2010.

  1. person_man

    Thread Starter New Member

    Oct 1, 2010
    This is my first post on this forum and also my first project where I am wiring without a layout for everything (I have done basic wiring on a guitar but that is very straight forward).

    I am wiring three motors and 2 motors will each have a DPDT center off switch and one will have 2 SPDT push button (all to control the direction of the motor) and they will all be attached to a 12 V power supply.

    I found this diagram for one motor on these forums [​IMG]

    My questions are:
    1. How would I wire the DPDT center off switches in this, from what I have found, you attach the + and - to the switch and then attach the motors to the switch also, would I use the same layout in the picture, in relation to this:
    Which side corresponds to which direction of the switch?
    2. Would I do this layout for each motor and just connect all of them to the same power and ground?
    3. Would the ground wire go to the negative terminal on the battery?
    4. I want 2 of the motors to stop after they turn a certain amount, how would I do this?
    5. I want to attach a LED to the control box to show that it has power, and I found a site that showed just a LED with a resistor attached to a power supply. Would I use a separate wire coming from the power supply and wire it accordingly or would I attach the LED and resistor after all of the motors so they wouldn't have reduced power?

    Sorry if I sound like I have no idea what I'm doing, because I really don't. Even some good reading would be great, I would appreciate any help
  2. SgtWookie


    Jul 17, 2007
    I drew that schematic in February of 2008 to help someone on here.

    Sure, that would work. That's a very common way to wire up a DC motor to reverse it's direction.
    It depends on the switch (bat-handle or slide), and which motor's lead you've connected where.
    With a bat-handled switch, the center terminals are connected to the terminals opposite of the switch handle position.
    With a slide switch, the center terminals are connected to the terminals on the same side as you slide the handle to.

    I suggest that you use a suitable fuse or circuit breaker for each motor circuit.
    Are they geared motors? If so, you will need to use (a) limit switch(es) and relays. If not, you need a different type of motor.
    You can simply connect an LED with a suitable current limiting resistor in series, across the + and - of your supply. Don't wire them in series with the motor wiring, or the motor won't run.

    That's what these Forums are all about. Nobody knew anything about electricity or electronics when they came into this world. It can be somewhat bewildering when you are "getting your feet wet", so to speak.

    It would help us to help you if you explain as best as you can what you are attempting to do. If you have specifications and/or manufacturer name and part numbers for your motors, that would also be a big help.
  3. John P

    AAC Fanatic!

    Oct 14, 2008
    You can have the motor run to a limit switch without using relays, if you use a diode. The switch would be a normally-closed type and the diode would be placed across its terminals, with the motor current running through the switch. The motor would run until it hit the switch, but then it would need current via the diode, so it could back away but not move any further forward. Common microswitches are SPDT, so they'd be usable in this application.

    There are also very low-power motors which can run into an obstacle and then allowed to stall without being damaged or drawing much power, but not everyone believes in them.

    Edited to say that you don't absolutely need the diodes. There are wires in Sgt Wookie's circuit and in the DPDT switch version which you could bring out to the limit switches, where if the switch actuated, you'd still be able to run the motor the other way. But for convenience, the diode scheme might be better, in order to have only two wires running to the motor and switches.
    Last edited: Oct 2, 2010
  4. person_man

    Thread Starter New Member

    Oct 1, 2010
    Hi, thanks so much for the helpful responses. My project is for school (it's a remote controlled submarine) and our teacher is very strict about electrical components we put in, we can only use what is provided and some other things.

    I will defiantly site you or this website (what would you prefer?) as my source for the schematic and all the help.

    Unfortunately, we only have one fuse for the entire thing so would I just wire everything to this?

    I'm not sure about the motor, all the parts list says is it's a 12v jameco motor, part #232022. I want the one attached to the rudder to only turn a certain amount, and I'm sure we can use a diode. I'm not sure how that works though
  5. John P

    AAC Fanatic!

    Oct 14, 2008