Hi there,
I am trying to drive an older stepper motor (Astrosyn Y163: Datasheet) using an A4988, but I cannot get it to work right, I have been following this guide: Guide and have it wired up as below:
I am running the test code provided by the guide, most of the time the motor either simply makes a noise or it judders back and forth, I thought I had it wired wrong (it's an 8 wire motor I wired to bipolar series 4 pin using the datasheet) however if I set the delay between step on and off to exactly 1900 it spins, sometimes, albeit very slowly and if I as much as touch the shaft it stops and just starts buzzing, I set the current limit vref to 800mV (Resistors on the board are 0.1Ohm and the motor is 1A) so based on the given equation this should be correct, I am supplying power from a bench supply at 12V (I have tried between 5-30 as the datasheet for the motor isn't clear) with a limit at 2A. I am really lost at this point as to what to try. (I have two drivers and two motors, I have tried combinations of both to rule out hardware issues) Anyone got any ideas? Please let me know if you need any more information.
You are driving 1/5 and 3/6 as one coil, and 2/7 and 4/8 as the other coil?
Maybe one or more coils are burned out.
Use a meter and buzz them out to make sure there is continuity thru all 4 coils, and that none are shorted to others.
I always use a multimeter to check the wiring of any stepper motor - motors with the same
part number come in a variety of winding options and there is no guarantee the wire colours
are standard.
Since its 8-wire how did you match up the two A windings and the two B windings? This can't
be done passively... Did you trust the datasheet?
Your symptoms suggest a problem with one winding set, perhaps you've series'd them back-to-back,
or mixed A and B windings?
To test a series connection apply 1A from a current limited supply to one winding set and check
this locks the motor hard. Then check the other winding set locks the motor hard at a slightly
different position. If the windings are back-to-back by mistake the position holding will be feeble.
Note the dots indicating winding direction on the diagram in the datasheet - they've actually drawn
the windings illogically placed, but the key detail is the dots.
I have the same problem with different motor. My Board is Arduino MEGA2560 Motor is QSH4218-41-10-035. I also use an A4988 too.
This is my simple code I tried.
const int Step=3; // STEP PIN
const int dir=4; // DIRECTION PIN
/*----------------------------SETUP FUNCTION--------------------------*/
void setup()
{
Serial.begin(9600);
pinMode(dir,OUTPUT); // DIRECTION AS OUTPUT
pinMode(Step,OUTPUT); // STEP AS OUTPUT
}
/*----------------------------LOOP FUNCTION--------------------------*/
void loop()
{
digitalWrite(dir,LOW); // SET DIRECTION LOW FOR FORWARD ROTATION
for(int x = 0; x < 1000; x++) // LOOP 1000 TIMES FOR 1000 RISING EDGE ON STEP PIN
{
digitalWrite(Step,HIGH); // STEP HIGH
delay(500); // WAIT
digitalWrite(Step,LOW); // STEP LOW
delay(500); // WAIT
}
delay(2000); // DELAY BEFOR SWITCH DIRECTION
digitalWrite(dir,HIGH); // SET DIRECTION HIGH FOR BACKWARD ROTATION
for(int x = 0; x < 1000; x++) // LOOP 1000 TIMES FOR 1000 RISING EDGE ON STEP PIN
{
digitalWrite(Step,HIGH); // STEP HIGH
delay(300); // WAIT
digitalWrite(Step,LOW); // STEP LOW
delay(300); // WAIT
}
delay(2000); // DELAY BEFOR SWITCH DIRECTION
}
I Ohm out the 2 coils, they are 9ohm. I try to connect motor to 5v DC by hand, step by step and Motor seem moves step by step (1,8 degrees)
I try 5 A4988 and had same results.
This is my video about my Motor. Motor does not rotate
I am new hear and this is the first time I try Arduino.
Its rediculously easy to blow up stepper drivers if the connections to the windings aren't
rock-solid - perhaps your breadboard has dodgy connector strip?
Thank MarkT for answering my question. Could you help me with the next question?
I tried to supply only Driver by a DC 5.5V 2A Max.
I only tried to suplly power for Driver A4988 like this picture
Connect DIR pin to GND (like pulling low),
-STEP pin to 5v output from Arduino,
-Also use the supply from Arduino to power the VMOT and GND (For Motor), just to check the Pulse out.
The result, there is pulse out from couple 1A,1B and 2A,2B, but the Motor does not rotate. I tried so many times to switch wires from Motor, but non of them works.
I hope that I was right about the Driver be burned. but I tried 5 of them, all are news, same results. I am so confused now.
This is wrong diagram, I think. I found out that the STEP pin should be pulse single (0-1, my vocabulary is not so good at this matter)
MarkT:
The A4988 has a minimum supply voltage of 8V.
Dear MarkT, I bought a new Driver - adafruit tb6612 which has Motor voltage range from 4,5V to 13,5V (My motor is 4,5V and I use 5V output from Arduino) . I also use exactly example from the homepage Guide
But my Motor moves only few steps, not follow the command, and vibrate really strong. I am guessing the Motor has problems themself. I could not buy a new motor the check yet.
I am searching in the forum about this matter, but if any of you have the method, please give me a comment.
wildbill:
It seems more likely that your breadboard is burned out - they're not built with stepper motor currents in mind.
Sorry, I do not understand clearly.
My motor is not a big one, also I use really small current/volt to run the motor.
I bought 2 breadboard to check them too :))) Just I did not buy an other motor and other Arduino yet. every thing I tried from two pieces.
