Communication PLC and sensor using RS 485

I am a beginner!!

I have a sensor which have only RS 485 port having three terminals 485+,485- and Ground. I want to communicate that with EZ touch PLC which have RS 422/485 port which contain RD-,RD+,SD-,SD+ and GND. I just jumpered RD- & SD- and SD+ & RD+. Connected RD- with 485- in sensor and connected and SD+ with 485 + of sensor. Ground of sensor is connected to the ground of PLC. But it is not communicating. I have sent data through RS 485 port through software. How would i know that data is sent through the port??

Please help me

Thank You

What is your sensor - brand/model? Give us as much information as you can -- don't make us guess...

another note one is full duplex one is half duplex the half duplex is the two wire setup the other is full duplex 4 wire or in other words has handshaking. the 4 wire setup may or may not be able to use half duplex but most likely it can and transmit goes to recieve so rd- to td- td- to rd- unless your using the null modem setup unlikely in your case. your going to have to find out which is the transmit the 485+ or the 485 - (very unusual nomenclature for a device what is it?)