using modbus tcp/ip to control vfd speed

[jmejiagusmer]

Hi, I'm brand new to Modbus and fairly new to LabVIEW. I do not have any code constructed yet, so I'm posting to here so that hopefully I can get led in the right direction. I have downloaded the free modbus library because after explaining to NI what I needed, they told me that this would give me enough functionality. I am trying to read the vfd frequency and display it on my front panel, as well as be able to adjust the frequency of the vfd through the front panel. I'm sure that this is a fairly simple and straightforward solution, but since I am brand new to modbus, I really am not sure what values I need to get in order to make this happen. I'm assuming that I need to initialize a tcp master, but what values do I need to feed it so that it can read anything from my vfd? I have an ABB ACS355 VFD with a FENA-01 ethernet adapter. I have the manuals for both and I see lots of parameters and numbers but I don't know how to make sense of them. Are there any keywords I should be looking for in these manuals? Sorry for posting such a general question but I really don't know how to begin this properly. Thanks in advance for any help!

[Blizzard]

Hello,

A great place to get started will be the shipping examples in the example finder. In LabVIEW, if you go to Help>> Find Examples and the search "Modbus" you will see and example called Modbus Fundamentals.lvproj. This uses shared variables and can communicate with TCP/IP (or ethernet etc) and is set to connect to the localhost. This example also shows how to read and write  using Modbus. There is a readme also included in the project if you need more information.

Additionally, there is a great getting started white paper that may be helpful for you. I've linked it below:

Introduction to Modbus: http://www.ni.com/white-paper/7675/en/

I hope this helps!

Best regards,

Anna L