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How to use Modbus on cRIO 9040 with serial port ?

Hello everyone,

I have recently started using LabVIEW with a cRIO 9040 and am still in the learning process.

I would like to use my cRIO with a Smartlink Modbus Slave (A9XMSB11 manufactured by Schneider).


So, I have two questions:

 

  1. I tried using the "Create Master Instance" VI to create a Serial Master Instance. However, I'm not sure what to specify for the "VISA resource name" input. I read that this corresponds to the port to which my Slave would be connected. Is that correct? What value should I provide?

  2. The Modbus output on the cRIO 9045 is a RJ45 type, but the Slave has an RS 485 input with 4 pins (D1, D0, Earth, GND). So, here's my question: What type of cable should I use to establish this communication?

I hope I have been clear in my explanations. I am available for clarifications.

Thank you for your answers.

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1. I tried using the "Create Master Instance" VI to create a Serial Master Instance. However, I'm not sure what to specify for the "VISA resource name" input. I read that this corresponds to the port to which my Slave would be connected. Is that correct? What value should I provide?

It is the Modbus Master port of RS-232 to which your slave is connected to. Make sure you have installed the NI-VISA driver on the cRIO. See Using the RS-232 Port on My cRIO

 

 

2. The Modbus output on the cRIO 9045 is a RJ45 type, but the Slave has an RS 485 input with 4 pins (D1, D0, Earth, GND). So, here's my question: What type of cable should I use to establish this communication?

You can purchase some adapters. For example

ZYOng_0-1693335596955.png

 

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