Pump control using inverter and LabVIEW

[Chowdhury_Milon]

Hi All,

I am trying to Start/Stop & frequency control of a LS SV-iG5A inverter through LabVIEW. I used RS 485 to connect that with computer.  I have attached a picture of communication specification of the inverter. When I connected the inverter with computer a COM port showed but I don't know how to make code now. I went through Introduction to Modbus using LabVIEW but can't find Modbus Master option in my LabVIEW.

Any suggestion about coding or any previous example code will be appreciatable.  

[GerdW]

Hi Milon,

why do you initialize a TCP connection when you want to use ModBus/RTU (aka serial COM port)?

[Chowdhury_Milon]

Hello Mr. GerdW,

Actually I was searching the coding process for the inverter. Then I found the Modbus example code. They suggested to use "Create Master Instance (TCP)". Sorry I thought both are same. Would you please suggest me some sample code for Modbus/RTU, please?

[GerdW]

Hi Milon,

change the polymorphic instance to "Modbus RTU" (or similar, I don't have that Modbus toolkit installed)…

I'm pretty sure that toolkit comes with example code and I guess there also is an example using Modbus/RTU!

[Chowdhury_Milon]

Hello Mr. GerdW,

Thanks for your reply. I have installed the NI Modbus Library, but I have some questions about LabVIEW modbus 

1. Is this modbus (pic_1) same for Modbus RTU and Modbus TCP?

2. My icons (pic_1) and some example vi's icon (pic_2) are different. Is it a problem?

[RavensFan]

The two pictures show two different modbus libraries.  But either will work.  The ones with the all white icons are the older library.  The ones with the purple header are the new library.

Both libraries have RTU (serial) and TCP (ethernet) versions.  The newer library is based on LVOOP classes.  The older one has different sets of polymorphic VI's to distinguish them.

[Chowdhury_Milon]

Hello Mr. RavenFan,

Greetings. Thanks for your reply. I want to control inverter through labview (Modbus RTU). I am in the preliminary stage. Would you give some some links or easy examples for starting, please?

[RavensFan]

Both of those libraries have examples built into them if you look in their respective palettes.

The purple library is under Data Communication >> Modbus Library.

The while library is under User Libraries >> NI Modbus