Control Eurotherm 2402 through RS232 port

[gq]

Hi all,

  I try to use example vi in ET24xx driver from NI's Example Code Library( Labview 7.1) to control a Eurotherm 2404 temperature controller over RS232 using ODBUS protocol.When native RS232 port is connected to controller, example vi works well. When a usb to RS232 adapter is used, an error message comes out,"Error -1073807339 occurred at VISA Read in ET24XX Utility MODBUS RTU Receive Message.vi->ET24XX Utility Write To Register.vi->ET24XX Select Setpoint.vi->Eurotherm Test.vi; Possible reason(s):VISA: (Hex 0xBFFF0015) Timeout expired before operation completed."

 If I delete "ET24xx select setpoint.vi" from code, Example vi works again.

  Does anybody can give an explanation to me?

Thank you in advance!

gq

[Albert.Geven]

your usb - serial port converter ha some extra settings or does not behave correctly at all.

Try to find one with an ftdi chip inside, these normally work correctly

[Adam G]

Hello gq,

I found a knowledgebase article that describes the error you are getting. You might be able to fix it by increasing the timeout. I am not sure why some of the examples are not working for the instrument driver you are using, but it is not NI supported so we have not done testing with it. Have a great day!

Best Regards,

Adam G