Continuity Tester

Hi Guys, I am working on a project at the moment for which I have to build a continuity tester to test

cables with 3-4 wires. I am really after a low resistance (<2ohms) ohmmeter but after some research I

haven’t been able to figure out an easy to implement solution.

I have couple of posts regarding continuity tester on this forum, but didn’t get a clear idea. Can you please

guide me. I have Arduino Mega board for prototype.

Thanks.

Hi,
If you need to measure the actual resistance then you may need some extra circuitry between the arduino analog input and the wires you wish to measure <2 Ohms.

If all you need is a go/no go system just looking at continuity then arduino_x solution would be easy to implement.

Thanks… Tom… :slight_smile:

Thank for your response.

You are right @Arduino_x solution seems easy to implement: I have attached a piece of code, is it this the

sort of arrangement you pointed to?

void setup()
{
  Serial.begin(9600);
}

void loop()
{
  pinMode(2,INPUT);
  pinMode(3,OUTPUT);
  digitalWrite(3,HIGH);
  if(digitalRead(2)==HIGH)
    Serial.println("Conducting 3 to 2");
  
  pinMode(3,INPUT);
  pinMode(2,OUTPUT);
  digitalWrite(2,HIGH);
  if(digitalRead(3)==HIGH)
    Serial.println("Conducting 2 to 3");
    
  delay(1000);
}

@TomGeorge if you have a schematics or a sketch of the circuitry I would need to build the ohmmeter,

can you please post it as I would still like to give it another ago.

Thanks.