AC Current Sensor

I am reading the analog values of ct sensor on arduino board using the analog serial read code. For different wires it is coming different but values are coming very less in mA(Main current in primary wire). I get the significant value of current i am using bigger burden resistance(470k ohm) but according to the calculation i can not use burden resistance greater than 35 ohm(For 100A ct sensor and 5v). So why the value of current is coming very small?

What's a "ct sensor"? Provide links to the hardware used and a wiring diagram of your setup.