Automated GC triggering from reactor

[atulchemistry]

Hello Friends,

I need desperate help in labview programming of my reactor and GC system.

I have a labview controlled reactor with temperature, pressure and flow parameters.

Also i have hardware in place to trigger the GC from RS 232 interface.

What i need to do, is to trigger the GC from labview when the specified process values achieved for temperature, pressure and flow.

And to count the number of triggers happened. And after given triggers it moves to the next setpoint for those parameters.

and then it continues.

e.g. I have setpoints for temperature like 200, 230, 250

then it should trigger the GC lets say 4 times for 200C and send signal to heater for next value which is 230 and once process value reaches 230 the same sequence again.

Its like giving programmed setpoints for specified triggers.

All the help will be highly appreciated !

Thanks in advance

regards

Atul

[atulchemistry]

Nobody is having any idea about this ?

Strange

[johnsold]

Atul,

You were not very specific in indicating the nature of your problem.  Do you need to learn how to program in LV? Can you communicate with the instruments but cannot control when things happen?  How does the user enter or select the setpoints and dwell time at each point?  What have you tried so far?  Do you get errors, and, if so, what are the errors?

Please post your code along with some typical data and specific indications of what the problems are.

Lynn

[atulchemistry]

Hi Lynn,

Attached you can see the logic diagram of this which i am intending to be preparing.

I am at early stage of learning labview due to which i have no clue from where to start for such type of control.

thanks

[johnsold]

Atul,

It is good that you have a clear logical description of what you want the program to do.

Since you are new to LabVIEW, look at the on-line tutorials if you have not done so.  They are a good place to start.  After that learn about state machines.  State machine architectures are very versatile and robust and are well suited to problems like yours.  There are examples which come with LV and many, many posts on this Forum.

Lynn

[atulchemistry]

Since then i was reading the tutorials about state machines.  At  the moment i can start and run simple state machines from the tutorials, but unable to get from where to start for my program.

If possible could you help me having one example for checking the setpoint and process values state machine ?

In this way i will understand what is required for my program.

Thanks

Atul

[johnsold]

I may be able to put something together for you.  Which version of LabVIEW are you using?

Lynn

[atulchemistry]

I am using Labview 2010 version.

thanks

Atul

[johnsold]

Atul,

Here is an example built from the Design Pattern for a state machine.  It can give you some ideas about how this could work.  For a real program connected to an instrument and a process heater, I would do a more elaborate program with added user interaction and safety features, probably based on the Producer/Consumer (Events) Design Pattern.

Lynn

[atulchemistry]

Many thanks !

Its great way to start for me and learn.

I will get back soon !

Thanks

Atul