software feasibiliity

[sunkara]

I would like to know as to what software in PLC programming can be compatible with labview.Can a PLC laader logic be implemented in LabView.

[tst]

LabVIEW is not comparable to ladder logic any more than C is comparable to ladder logic. LV is a high level language, much more than ladder logic.

You can obviously write program in LV which will do anything that a PLC program does, and it will be much more powerful and easier to write, but you won't be able to download the code to a PLC. You will need something which will run LabVIEW. This can be either a standard PC, which is usually reliable if it is kept properly and not installed with all kinds of garbage or, if you need a real-time solution, you can get either a real-time desktop PC or NI's PAC, Fieldpoint, which also runs LV real-time. PACs in general, and Fieldpoint in particular, have much more computing power and options than standard PLCs. They also cost more.

The advantages come in abilities and productivity - you can perform better on a FP and you can write more complex code much more quickly than in ladder diagram. You can also do very easy integration into a factory network of computers to pass data around etc. The thing is that you need to get some experience in LV to properly write a real-time application. Most applications will work properly, but you might run into some problems if you don't know how to do it.

If you give more details about what you actually want, we could give you more details.

[sunkara]

Hi

Thanks for the reply.Well i am looking to do a project in PLC .I have E-series PLC from Tri-logi.I would like to know how PLC can be done in labview.I was trying to find some examples simulated in Labview.I am looking into implementing Ladder logic technique to some process .Can any one send in few examples in understanding design of PLC using lab view and can i integrate Above controller using labview

[preston_johnson]

If you are definately going to use the PLC for the I/O and sequencing of functions, then LabVIEW becomes the HMI or Graphical User Interface for the PLC.  You can communicate via Modbus directly to the PLC from LabVIEW.  This of course requires that your PLC is able to speak modbus.  The alternative is to get an OPC server from the PLC vendor, and use LabVIEW as the HMI thru the OPC server. 

If you want alarms, trends, events, and industrial graphics, you might also look at the LabVIEW DSC Module

[sunkara]

Sir,

Thanks for the message.I learned labview on my own in india ...i have knowledge of basics .But i would like do implement PLC ladder logic in labview simulate and see the results.i just have the software with me .Where can i find examples for practice in NI.Your answer was perfect.I am a student and so i cannot get in a server.Well my prof. would buy the necessary infrastructure if i am able to tell him whether it is possible to integrate Labview and Tri logi PLC (E Series) then he may get in the necessary things .This would even create new platform for other students to do good projects

[tst]

It is unclear whether you want to simulate a PLC using LV or whether you want to transfer data from the PLC to LV.

The first thing to understand is that LV is not a ladder logic language and you can not use it as it is to talk to those PLCs (although their site does say that the M series supports Modbus and even mentions NIs Lookout as one of the tested packages).

What you can do is use the simple ASCII protocol supplied in their site to transfer data between LV and the PLC. You will need to write VIs which will use the serial port VIs to communicate with the PLC and pass data (like I/O, timers and such) between LV and the PLC. You can search the example finder (Help>>Find Examples) to find serial examples. You can also search for various Modbus examples on this site to see how this can work.

Writing a simulator is a whole different deal and is probably something you will not want to do without knowing a lot more than you currently know.