So I have a Nema 17 rated at 44Ncm, and a Nema 23 which is rated for ~160Ncm, and then I have a L298N driver, a A4988 driver, and a TB6600 driver. The problem I am having is that when I using the A4988 or the TB6600, I can't get it to pull more than about 0.26 amps; the torque is really bad.
With the L298N driver I get good torque, and I can see on my power supply that it's supplying 2 amps (what I've currently limited it to), when it runs (or even just holding). The L298N has 4 wires going from the the controller to the arduino, and I run it using the Stepper library:
#include <Stepper.h>
const int stepsPerRevolution = 200;
Stepper myStepper(stepsPerRevolution, 8, 9, 10, 11);
void setup() {
myStepper.setSpeed(200); //revolutions per minute
}
void loop() {
if (Serial.available() > 0) {
int steps = Serial.readString().toInt();
myStepper.step(steps);
Serial.print("Stepped: ");
Serial.println(steps);
}
}
This is great, but the L298N is only rated for about 2 amps, so I don't want to push it past that. I can run the Nema 23 on this same setup, but I don't get any extra torque, because I'm limiting to 2 amps at the power supply.
When I switch to the A4988 or the TB6600 I get the same results (whether I am driving the Nema 17 or the 23). Whether I set the power supply to 12 or 24v, the power supply says it's only pushing about 0.26 amps, and the torque isn't there.
Based on all the youtube videos I've watched, it seems you only control the driver via 2 signals, pulse, and direction. I've tried the examples from the accelstepper library, and I've also tried going library-less with similar results:
const int stepPin = 3;
const int dirPin = 4;
void setup() {
pinMode(stepPin, OUTPUT);
pinMode(dirPin, OUTPUT);
digitalWrite(dirPin, HIGH);
}
void loop() {
for (int x = 0; x < 2000; x++) {
digitalWrite(stepPin, HIGH);
delayMicroseconds(500);
digitalWrite(stepPin, LOW);
delayMicroseconds(500);
}
delay(1000);
}
I'm running both drivers in full step mode. I've tried playing with the speeds, and making sure I'm not going to fast, but even when just holding, I would expect to have something close to 2 amps with all of these drivers when driving the Nema 17. I've tried playing with the potentiometer on the board, and that doesn't seem to make any difference. If I play with the current limiting switches on the TB6600, I can make the board pull less current, but not more. It seems that 0.26 amps is about the max.
Is there some fundamental I am misunderstanding? Or any ideas of the next steps to troubleshoot this? I've ordered a couple DM542 drivers, but I'm not really holding my breathe.
Thanks!
