0

I was trying to drive a single dc motor with L293D Shield and Arduino Uno

#include <AFMotor.h> #include <SoftwareSerial.h> AF_DCMotor motorLeft(3); AF_DCMotor motorRight(2); unsigned char opMode = 0; void setup() { } void loop() { motorLeft.setSpeed(30); motorLeft.run(FORWARD); delay(5000); motorLeft.setSpeed(0); motorLeft.run(RELEASE); delay(5000); }

When I turned the power on, a beep sound was made continously. As I was trying to figure out where the sound comes from, I smelled something burning and turned the power off.

I am giving 6V (Four 1.5V batteries in series) as external power. Burning smell doesn't come from batteries, that's for sure.

The smell comes from arduino or shield or both. But I think it is the the left LM293D driver.

What did I do wrong? Any idea?

Improve this question
4
  • 1
    Please show a schematic, or at least a wiring diagram. This doesn't sound like a code problem. Commented Mar 22, 2020 at 13:03
  • @JRobert The shield is not supported by fritzing so it is a little bit hard for me to create a schematic. But it is pretty simple. 6V is connected to EXT_PWR of the shield (Of course there is a switch in between), and DC motors are wired to M2 and M3. The polarity doesn't matter here as far as I know. There is nothing else. I have checked the polarity of the battery via multimeter. It is correct. Commented Mar 22, 2020 at 14:10
  • What happens if you power up the system with the motor(s) disconnected? With motor(s) connected but 6v disconnected? You need to partition the system some way until you can narrow down the source of the short-circuit. Obviously, keep the powered-on time as short as you can to limit any (more ): damage while you're testing. Commented Mar 22, 2020 at 16:16
  • I did two things: I increased PWM from 30 to 255 and I took the PWRJMP jumper out. Now my card works totally fine. However, now I have to get power from both USB and batteries. Since I am trying to build a robot at the end, it is a problem. I am afraid to try with the PWRJMP on. Commented Mar 22, 2020 at 17:42

1 Answer 1

Reset to default
0

Alright, I finally realized that RPM value was too low. It has to be at least 150 for my case.

Improve this answer

Start asking to get answers

Find the answer to your question by asking.

Ask question

Explore related questions

See similar questions with these tags.