I am learning the Arduino using the SparkFun inventor kit guide. and I am on circuit 12 which is just controlling the toy dc motor using transistor as a circuit.
Everything seems to worked but this dc motor seems to just work intermittently.
Sometime it will work then sometime it won’t work at all.
Any idea why??
When I measure the current going through the dc motor, I can see the current is flowing through the motor and I can hear a small hum in the motor but it is not turning.
You may not be getting enough power to the motor. I would recommend checking your connections. If there are any loose connections anywhere in your circuit (between the Arduino and the transistor, or the transistor and the motor), you may see some odd behavior. Also, make sure the leads into the motor look like they are connected well. You might want to try switching to a different spot on your breadboard as well. We have seen issues before with continuity problems in the breadboard itself, so it’s worth checking.
I’m not sure what the circuit you’re trying to do (a link would have been nice) has for the base transistor (CIRC-12 is LEDs) but if it’s like the above, the base resistor is too large. Make it more like 330 ohms.
The DC toy motor I purchased required a lot more current then others. Sparkfun sells 2 kind, one with just 70mA spec as no load current and the other one is 320ma no load current.
The circuit is not giving enough current into the bigger motor and it seems to work if I change the speed instantaneously instead of gradually changing it.