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How do you wire a 12V dc motor for forward and reverse using 2 micro switches.? Please draw diagram


Willard2.02 years ago
Check out the MAG speed control on this page, I think it's exactly what you're looking for. I have used it with great results.

The way it's wired, you press one switch for forward, the other for reverse. It is the same wiring as Steve's drawing, but with a little bit more detail. 

Rick's design requires you to press both switches to reverse direction and there is no 'off' position.
MAG.gif
need help with where i would need to put a rheostat for speed control this works perfect for me just dont know where the rheostat goes for the speed control thanks
I would be inclined to put the rheostat between one of the motor leads and the switch (1), or between a battery lead and the first switch (2).  Anywhere else, and I don't think it will control the speed for both directions.

I haven't worked with rheostats before, but I *think* that is where you'd place it.
FOMSWXBH0FLNZM1.LARGE.gif
hello again is it possible to use an analog stick from a ps2 or from any controller with a joystick i dont need it to turn left or right or anything i just need it to go forward and reverse is there a way to do this and if so what would i need thanks once again
I dont know of a way to do it without a micro controller like the arduino. Im sure there is a way. I would post a new question, there are many members with much more experience than me and they should be able to point you in the right direction.
thanks mate
This is the same diagram as used for house lighting where you have stairs and want to turn the light on or off from either the top or the bottom of the stairs. It works fine and will work in this situation as long as there is a common terminal on the microswitches
Yours also requires that both switches be pressed for one direction, and both diagrams have the off position where you've only pressed one of 'em.

L
The motor is off when both switches are in the same state (pressed or released), the motor is on when the switches are in different states.

With both switches open, negative is connected to both terminals of the motor (thus, the motor is off).
Press one of the switches, positive is connected to that pole of the motor (remember the negative is still connected to the other pole, the motor spins one way).
Press both switches, positive is applied to both motor terminals, and the motor is off.

Rick's requires both switches to be pressed to change directions, and one pressed to stop.  Steve's is the same as my diagram.
The truth-table is the same for all of them, you've not seen that yet.

L
theoldguy2 years ago
Don't - you will forget one day and burn out the motor. Use a double pole switch.
How will you burn out the motor ?
rickharris2 years ago
Same diagram drawn slightly differently - It's called An H Bridge.
Try this.
Copy of motor uswitch.png
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