# 4 stepper motors, 4 l293d, and 4 t100 thrusters

Hello,

I am trying to run 4 Nema 14 stepper motors through 4 l239d H-bridges to my Arduino mega 2560. They are pivoting my t100 thrusters on my AUV. Im currently just using a DC power source to energize the circuit so my amperage and voltage are adjustable but im afraid to turn up amps or volts too high. Am I correct in thinking that if the 4 steppers are .8a then its safe to turn up to 3.6a and use around 12 volts(12v Steppers, also the battery I hoped to use is 12v 7amps)? Right now the t100 will run but the stepper motors don't have enough torque and just vibrate.(Ive checked wiring a lot and pretty sure the poles are correct).

Below is the main portion of code controlling steppers

const int stepsPerRevolution = 200;

const int step1p1 = 30;

const int step1p2 = 28;

const int step1p3 = 26;

const int step1p4 = 24;

// SECOND STEPPER
const int step2p1 = 31;

const int step2p2 = 33;

const int step2p3 = 35;

const int step2p4 = 37;
//THIRD STEPPER

const int step3p1 = 39;

const int step3p2 = 41;

const int step3p3 = 43;

const int step3p4 = 45;
//FORTH STEPPER

const int step4p1 = 47;

const int step4p2 = 49;

const int step4p3 = 51;

const int step4p4 = 53;

Stepper myStepper(stepsPerRevolution,step1p1,step1p2,step1p3,step1p4);
Stepper myStepper2(stepsPerRevolution,step4p1,step4p2,step4p3,step4p4);
Stepper myStepper3(stepsPerRevolution,step3p1,step3p2,step3p3,step1p4);
Stepper myStepper4(stepsPerRevolution,step2p1,step2p2,step2p3,step1p4);

Void setup() {

myStepper.setSpeed(20);
myStepper2.setSpeed(20);
myStepper3.setSpeed(20);
myStepper4.setSpeed(20);

{

void test1 (){

Serial.write("test1");

servo1.writeMicroseconds(1600);//Front left

servo2.writeMicroseconds(1600);//back right

servo3.writeMicroseconds(1600);// back left

servo4.writeMicroseconds(1600);//back right

delay(1000);

void Descend(){

Serial.println(" clockwise");

myStepper.step(stepsPerRevolution/4);
myStepper2.step(stepsPerRevolution/4);
myStepper3.step(stepsPerRevolution/4);
myStepper4.step(stepsPerRevolution/4);

delay(1000);

}

The important thing for a power supply is that it should provide the correct voltage and more current than will be required. Assuming a device is powered with the correct voltage it will only draw the current that it needs. If your power supply cannot provide the required current the voltage will fall and the power supply may be overloaded and damaged.

If you want help with a program then please post the complete program and use the code button </>

``````so your code looks like this
``````

and is easy to copy to a text editor See How to use the Forum

You should also tell us in detail what the program actually does and what you want it to do that is different.

also look up the AccelStepper library

I tested the motors as you suggested with the required voltage and little more current. It made my H bridges smoke. I’m assuming the steppers drew more current then the H bridges could handle. I thought this would happen but trusted your response. Hurtin.

cjm803:
I tested the motors as you suggested with the required voltage and little more current. It made my H bridges smoke. I'm assuming the steppers drew more current then the H bridges could handle. I thought this would happen but trusted your response. Hurtin.

It is hardly my fault if you chose unsuitable h-bridges.

And how did you decide what the "required voltage" should be?