stepper motor problem

Using Arduino Motors, Mechanics, Power and CNC
1

I was using easydriver to control a stepper motor and a 9v battery. The motor specs are here in portuguese: RoboCore: Bloqueio de Segurança

it is refurbished.

9v and 2A /phase

it was working fine but stopped. I started with theses values:

digitalWrite(x, HIGH);
delayMicroseconds(10); //A
digitalWrite(x, LOW);
delayMicroseconds(300); // B

Then I tried increasing the delay, 20 microseconds for A and 3000 for B, and it worked for a while. But now the motor doesn't turn anymore. And I can turn it by hand with almost no effort, it wasn't like this before. There's almost no torque anymore.

What I'm doing wrong? Should I buy a new one?

Thanks in advance.

2

What are you using for the 9 volt source?
10us, way to fast!!

3

Also schematic please...

4

Not many 9V batteries can supply 200mA, let alone 2A....

That stepper is rated at 2A per phase and 2 ohm winding resistance - therefore it needs 4V, not 9V.

I suspect the 9V is the voltage for bipolar operation (two windings in series).

5

Dead Battery.