How to spin a DC Motor

Community Projects
1

Hello,

We are just a couple of DIY noobies here! We recently purchased some parts from Sparkfun and now we’re testing our hands at soldering and throwing together a tiny project.

Here is a picture of our setup:

https://www.dropbox.com/s/bhl1njll7tqzi … 3.jpg?dl=0

However, the motor does not spin with the 9V battery hooked up via the DC barrel jack. Can anyone help us out?

We’re using a 330 ohm resistor in series with the motor.

Thanks!

-Kepler

2

The 330 ohm resistor is one problem – leave it out. A 9V PP3 battery does not have the capacity to power most motors for more than a few minutes, if at all. It should run the one in the photo for a little while.

3

9v batteries are really crappy. Get a 4xaa or aaa box.

What kind of motor is it and what do you want it to do?

4

Ah, okay - not enough current getting through. I’ll look into getting a 4xAA box. Can I use a transistor to bring up the current supply?

At the moment we’re just messing around, but I was hoping to 3D print a little car and have this drive it.

Thanks for the replies!

5

Those copper wires look like they have some sort of coating. The fact that the motor is not running may simply be there is no conductive surface making contact in the breadboard. Apply a bit of heat to the ends to burn it off.

6

So I took my trusty multimeter to it and there was no voltage drop across the motor leads. There was voltage being provided by the battery.

I checked for a coating but can’t see or feel any - heating the end didn’t appear to affect it either. I’m thinking the problem may be in the soldering on the motor end? It was soldered by us (noobies) so we may have messed up and need to rework it.

Thanks for all the help!

7

JohannesKepler:
So I took my trusty multimeter to it and there was no voltage drop across the motor leads. There was voltage being provided by the battery.

As a motor runs because of current it is better to measure that. Set it to current mode (highest range), plug the red probe in the appropriate hole. And connect both probes in your circuit as replacing one of those wires (or the resistor that you had previously).

…

I checked for a coating but can’t see or feel any - heating the end didn’t appear to affect it either. I’m thinking the problem may be in the soldering on the motor end? It was soldered by us (noobies) so we may have messed up and need to rework it.

Thanks for all the help!

If the wire isn’t coated and is bare then when the 2 wires touch you would have a short circuit and things would start to heat up because of massive current. You are doing risky business on that table if it doesn’t have at least some sort of coating. Set the meter to resistance measurement. Take a piece of that wire and put both probes at points along the middle somewhere. Does it measure a resistance or not. If no resistance (0.0 something) then it is bare. If it measures a high resistance or out of scale indicator then it is coated.

Check to see if the holes you put the wires (and the resistor) actually were connected. The 5 holes on each side of the middle are connected together, but not connected to the other rows of holes along the length of the breadboard. Though the photo in the first message seems good.