DL-05 & Eurotherm Modbus Comm.

I am new to this stuff and am trying to set the temperature setpoint on a 3216 eurotherm through the use of a DL-05 plc. Does anyone have experience in coding this in Directsoft5 software? I am setting the temperature in the plc at v memory location 150 and am then trying to send the data to the eurotherm. Any tips or suggestions? I can't seem to get it to work.

V150 is in the middle of the timer current value memory range. See page 4-28 of the DL05 User Manual.

Please post the code segment(s) that you are using to communicate to the Eurotherm so that we can see what you are attempting to do.

I am using Directsoft 5 software to write the program for the PLC. I am also working with tech support from the company where I purchased the PLC. I know I have everything programmed correctly the only thing that I am not sure of is when I use an IBOX 702 Write command I am not sure on the slave address to use. I contacted the eurotherm tech support and they told me I needed to write to address 26 but the directsoft write IBOX only lets me use addresses the begin with the data type C,V,X,Y, etc.. The status lights on the PLC show it sending out a signal but no signal is being received back. This leads me to think that it is at the eurotherm end or I do not have the correct address in the IBOX 702 of the program code. Does this help you understand what my problem is? Any suggestions?

Do you have a link to the Modbus comm manual for the 3216?

MODBUS address 26 is GY31, but that is a coil address not a holding register. Holding register 40026 is probably what they meant which is V31.

See the handy MODBUS conversion spreadsheet.