Trouble using a generic 4-20mA to 0-5V board to connect transmitter to Arduino
Your loop powered (two wire) transmitter + sensor has two leads, call them S+ and S-. 

You need to connect one end of your two-wire sensor to the +24V (S+) and the other side (S-) to the + current input. No connection to the - current input (it's common with the power supply ground). 

The two-wire sensor needs a power supply and you are not giving it any. 





You should adjust the pots to ensure that  you don't get more than 5V out of the outputs before connecting it to the Arduino. It would also be a good idea to clamp the output in case there is a fault with the sensor but that's outside the scope of this answer.