TA12-100 Current Sensor (increase range)
It’s the opposite. You need to decrease the resistor to increase the range, up to a point.

The resistor loads the output winding of the transformer and is reflected back into the circuit reduced by the square of the turns ratio. A smaller resistor is equivalent to a smaller resistance in series with your load. 

However, if there is a metal/ferrite core in this sensor (I believe there is) this core will saturate with higher currents (particularly any DC component which it does not measure). So make sure not to exceed the current specification of the sensor.