Go Down

Topic: Smoke from the motor shield (Read 3786 times) previous topic - next topic

HellenT

Hello

I have motor shield bought from ebay which is the clone for adafruit motor shield V2

It works fine until I was trying to connect power supply(12V,2.5A) to both of the motor shield and the Arduino Mega..immediately there was smoke from the sheild.

Then i try to connect the Arduino mega to PC but my PC wont recognize it. Why is it happen? Isnt the Mega can accept 12V?and why the shield blow up? I dont have any idea..

MalharD


Where did you connect the 12v supply ?
In the barrel jack ?
The magic smoke has escaped. I doubt that the shield will work again.
Can you provide a link to the shield ?
-Malhar
Murphy always gets me ...

jremington

Undoubtedly the wiring was wrong, but without an accurate circuit diagram, no one can help.

MalharD

as TomGeorge says
Quote
Everything runs on smoke, let the smoke out, it stops running....
Murphy always gets me ...

Ralph_S_Bacon

#4
Apr 10, 2016, 06:32 pm Last Edit: Apr 10, 2016, 06:32 pm by Ralph_S_Bacon
One of the (very knowledgeable) contributors on this site has a signature that states that everything runs on smoke - let the smoke out and it all stops working. Was he right?

That tongue in cheek comment aside, you need to post (a hand-drawn) circuit diagram of your setup - now what it should be, but what it really is.

If your PC no longer recognises the Arduino Mega (when powered via the USB) you may have a terminal condition with that device. Measure the voltage when connected to the USB at the 5.5V and 3.3 V pins - are they what you expect?

EDIT - Gawdang beaten to the punchline by TomGeorge!
My YouTube Arduino Videos: https://www.youtube.com/RalphBacon
Arduino and electronics videos designed to get your project off the ground.
Dog Walking and Pet Sitting in Northampton: www.wagnificentpetcare.co.uk

Grumpy_Mike

The motor shield has two power inputs. The first is for the logic circuits and must be 5V. The second is the power for the motor and can be higher. But if you connect both to 12V you will put 12V on the logic pins of both the shield and the Arduino pin and yes this will destroy both.

HellenT

#6
Apr 11, 2016, 07:17 am Last Edit: Apr 11, 2016, 07:26 am by HellenT
Here is the schematic diagram

Initially, the circuit looks like this:



I connect both SCL and SDA to the Arduino. But the motor driver didn't work until I connected 5V and GND of the Arduino to the motor driver(even tho the motor driver was powered by 12V plug and I dont know why I must connect 5V and Gnd between the driver and the arduino). At this time, I powered up my mega using PC and my motor driver using plug

Then, I dont want my mega to be connected to the PC and want test my power supply to supply both of the Arduino and the shield. Because I am doing a project where both of the motor driver and my Arduino mega will be powered up by a better, so this is just for testing purposes. Here is the schemetic diagram after I connected the power supply to both of the motor driver and the arduino.




I connect the 12V plug cable to the screw terminal connector of the motor driver. Then I connect a jumper from that same screw terminal to the Vin and GND for Arduino Mega.

Grumpy_Mike

No diagrams! Read the how to use this forum sticky post for how to post pictures.

You need to connect the power and ground to the motor shield so you can send control signals to it. You need also to supply power at a higher voltage to the motor.

HellenT

Really sorry..there was something wrong with the link that I copied..now I have edited the post :D

Thank you so much

Boardburner2

#9
Apr 11, 2016, 07:46 am Last Edit: Apr 11, 2016, 07:59 am by Boardburner2
You show a 5v connection between the motor shield and the board.

Post the details of your motor shield (link).

That 5v i suspect is an output from the motor board, have you measured the voltage on it.

In your second diagram the + supply is connected to ground on the mega and the - supply is connected to another ground on the mega.

You have probably blown a ground track off the mega.

I connect the 12V plug cable to the screw terminal connector of the motor driver. Then I connect a jumper from that same screw terminal to the Vin and GND for Arduino Mega.

That is not what your diagram shows.

If by Vin of the Mega you mean the barrel connector then you have the jack supplying 5 v to the mega  and also the motor board supplying 5v to the mega also, bad idea.

HellenT

Sorry

There was an error with the 2nd diagram. Here is the updated one



And here is my motor driver.

I haven't measure the voltage yet from the 5V output of the motor board. But when I connect 5V of mega and 5V of shiled together according to the first diagram, the board will not power on if i didn't connect the shield to the PC

Boardburner2

I haven't measure the voltage yet from the 5V output of the motor board. But when I connect 5V of mega and 5V of shiled together according to the first diagram, the board will not power on if i didn't connect the shield to the PC
The adafruit stack shield FAQ says that only the motor board OR the arduino should be powered.

Documentation is poor.

You need to check if there is 5 V output by the motor board when it is powered up.

I have had problems with clone motor boards before with specifically this problem.


HellenT

I read about that but i thought that is only applicable if the board is attached to the Arduino. But i didn't attached the Arduino and the board together

Boardburner2

But you did connect the 5 v lines

HellenT

So how should I connect the shield and the Arduino?

and how do I supply current to both of them?

Go Up