3.5mm Jack & Current Transducer

Hi all,

I've got a 100A CT for AC current monitoring and I'm running a very simple AnalogRead script (below) to check functionality however I'm not getting any response. I've set it up as per the OpenEnergyMonitor schematic and have put the clamp over an extension cable while running a kettle, hifi, lamps and my monitor so there should be adequate current draw to register some sort of AC waveform.

I'm using this 3.5mm jack and figured this might be the cause of the problem. The connection through the breadboard is good and I've tried reading tip, ring and ground pins but still nothing. Any suggestions as to what might be the issue?

Code:

int i;
int z[250];
unsigned long t[250];

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

void loop() {
  for (i = 0; i < 250; i++) {
    z[i] = analogRead(A0);
    t[i] = micros();
    delayMicroseconds(8);
  }
  for (i = 1; i < 250; i++) {
    Serial.println(z[i]);
    //Serial.print("\t");
    //Serial.println(t[i]);
  }
  delay(1000);
}

Use a multimeter to check continuity of the connections, and to measure the output voltage from the CT circuit.

and have put the clamp over an extension cable

Over both wires? Only one wire can go through the current transformer or the opposite current through each wire will (mostly) cancel the magnetic field.

DVDdoug:
Over both wires? Only one wire can go through the current transformer or the opposite current through each wire will (mostly) cancel the magnetic field.

Of course! Thank you, been a long day...

And if you want more sensitivity you can put the wire though the center multiple times. For each pass through the center you get an addition output.

i.e.
5A through once looks like 5A at the output
5A through 3 times looks like 15 A at the output