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Author Topic: Problem powering more than one ESC with Battery Pack  (Read 487 times)
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Alright, so I am powering two ESCs from a 14.8v 5A lipo battery pack and when I send a pulse width through the PWM pins, the voltage being sent to the ESCs drops all the way down to 2v and then 0v.  Is my battery pack insufficient?
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Alright, so I am powering two ESCs from a 14.8v 5A lipo battery pack and when I send a pulse width through the PWM pins, the voltage being sent to the ESCs drops all the way down to 2v and then 0v.  Is my battery pack insufficient?

You really should post your code. Hopefully you are using a servo library to output commands to the ESC?

Lefty
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Oh yeah here's my code:

Code:
#include <Servo.h> 

Servo myservo1;  // first motor to be controlled by potentiometer
Servo myservo2;  // second motor to be controlled by potentiometer

int potpin = A0;  // analog pin used to connect the potentiometer
int potValue = 0;    // variable to read the value from the analog pin 
int mappedValue = 0;    //variable to hold "mapped" value

void setup() 
#include <Servo.h> 

Servo myservo1;  // first motor to be controlled by potentiometer
Servo myservo2;  // second motor to be controlled by potentiometer

int potpin = A0;  // analog pin used to connect the potentiometer
int potValue = 0;    // variable to read the value from the analog pin 
int mappedValue = 0;    //variable to hold "mapped" value

void setup() 

  Serial.begin(9600);          //  setup serial
  myservo1.attach(6);  // attaches the servo on pin 9 to the servo object
  myservo2.attach(9);
  Serial.println("The count down");
  Serial.println("5");
  delay(1000);
  Serial.println("4");
  delay(1000);
  Serial.println("3");
  delay(1000);
  Serial.println("2");
  delay(1000);
  Serial.println("1");
  delay(1000);
  Serial.println("0");


void loop() 

  potValue = analogRead(potpin);    // reads the value of the potentiometer (value between 480 and 990)

  Serial.print("potValue = ");
  Serial.println(potValue);             // debug value

    mappedValue = map(potValue, 0, 1023, 0, 179);     // scale it to use it with the motor (value between 28 and 179) 

  Serial.print("mappedValue = ");
  Serial.println(mappedValue);
  Serial.println(" "); 

  myservo1.write(mappedValue);        // sets the motor speed according to the scaled value 
  delay(125);                           // waits for the motor to gain speed 
  myservo2.write(mappedValue);
  delay(125);
}
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What kind of ESC, have a link? Arduino version? Wiring diagram?
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Wires the code:

http://www.hobbyking.com/hobbyking/store/__6459__Hobbyking_SS_Series_40_50A_ESC.html

I'm using an arduino duemilanove.
I can't post a diagram at the moment but I can say that I can get one motor working just fine, but I just can't get two to work.
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Sorry for the double post, I didn't see an edit button but that link is the ESC.
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What I can tell, based on schematic provided on web-site, there is a resistor 4.7 k is series with PWM input of the controller. There is no reason for voltage to drop noticeable, and if it the case, than something wrong with wiring or ESC failed. ESC programmable, probably you should use manufacturer hot-line technical support.
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So there's really nothing else it could be?  I guess I also might try and find a new battery just incase.
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Would the C rating of the battery have any effect on this sort of stuff? I believe that is the discharge rate.
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Would the C rating of the battery have any effect on this sort of stuff? I believe that is the discharge rate.

Yes, C is the discharge rate.  However, I don't think that would be the issue.  The ESC's current rating is 40 A, unless your battery pack has a  Total Capacity / C Rating greater than 40 A it shouldn't be able to harm the ESC.

Edit: Originally typed the math wrong and didn't notice it. smiley-red
« Last Edit: August 08, 2012, 05:19:31 pm by Far-seeker » Logged

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Should I probably just buy a new battery? Because I was able to get working fine with one motor and one ESC.
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