MotorShield v2.3. not working

[andresruelas]

Hello, I recently purchased an Adafruit Motor Shield v2.3

I am using an Arduino Uno and 9V external power supply. First I tried to connect my Nema17 stepper and nothing worked. StepperTest code didn't pass from "StepperTest!" part (Displayed on the Serial Monitor).

Later, I connected a 28BYJ-48 5V Stepper Motor, and again, nothing happen... the code again didn't pass from the first part. (I'm running the code exactly)...

What can I do??

Andres.

[adafruit_support_bill]

Please post photos showing your soldering to the shield.

[andresruelas]

:)

[adafruit_support_bill]

It looks like you have a number of cold joints and some that have not flowed onto the solder pad. This guide has some tips on fixing these:
https://learn.adafruit.com/adafruit-gui ... n-problems

[andresruelas]

Thank you!!!

When I connect the power the green LED start flashing, and I used 2 servos in the servo pins and they worked great...

So where exactly are the cold joints?

Again, thank you so much..

Andres

[adafruit_support_bill]

When I connect the power the green LED start flashing

It should be steady on. What power supply and motors are you using?

So where exactly are the cold joints?

Cold joints are the dull and/or lumpy looking ones. Please read through the link posted above. It has several photos of cold joints.

[andresruelas]

Sorry, it's steady on. I'm using a 9V Adapter and this NEMA17 stepper: http://www.ebay.com/itm/320842713273?_t ... EBIDX%3AIT

So the problem should be on the joints??

thank you

[adafruit_support_bill]

You should touch up the joints to assure good conductivity. But you cannot use that motor with ths shield.

With a 2.3 ohm phase resistance and a 9v supply, the motor will draw nearly 4A per phase. That is much more than the 1.2A continuous rating for the shield. From the specs, that motor is designed to be driven by a current limiting "chopper" driver such as the gSheild.

https://learn.adafruit.com/all-about-st ... he-stepper

[andresruelas]

But the specs of the motors says that:

Rated Current/Winding: up to 1.4A , and the shield has a 1.2 continuous rating and a 3A peak. So why it shouldn't work?

[adafruit_support_bill]

Rated Current/Winding: up to 1.4A , and the shield has a 1.2 continuous rating and a 3A peak. So why it shouldn't work?

Two reasons:

1) The rated current may be 1.4A, but the phase resistance is 2.3 ohms. Ohm's law says that feeding it 9v will result in a current of about 4A/phase.

2) With a constant voltage driver the current draw is nearly constant, so you need to use the continuous rating of the shield.

This is all explained in detail in the link posted above.