Controlling AB 1756 ControlLogix with Labview

[msu]

Hi,

  I want to use Labview instead of RSlogix to control and program the AB PLC (logix 5000), Is this possible? if not why is the Supervisory module used for? I have gone throught the forum postings but wasnt much of help. I need help regarding this one  (I  am novice at Labview)

Thanks in advance

[EFranz]

Hi msu

              You can communicate with your PLC trough labVIEW with OPC SERVER.

This , acts like a driver of your PLC and labview.

you can find more information about this topic and the available (most common at least) OPC server's links

here:

http://digital.ni.com/public.nsf/websearch/13EE0A9E2C43F0DB86256A6100722651?OpenDocument 

I hope this helps you a little to run your application succesfully.

[Tunde_A]

Hi,

Communicating with the AB PLC requires a server and client system. The server will be an OPC Server. There is a National Instruments Industrial Automation Server for communciating with Allen Bradley contained in the Industrial Automation Server CD. This server basically interfaces with the AB  RSLinx for publishing the data members of the PLC. LabVIEW can then serve as a client software that can access the published data using the LabVIEW Data logging and Supervisory Control (LVDSC) module. This DSC module basically allows you to create shared variables that can be binded to the published data from the OPC server. You can then perform further processing with LabVIEW on the shared variables and also log the published data to a database.

Checkout the following links for more information on communicating with AB  and getting started with LVDSC.

Tunde A.

[andysibley]

Hi everyone,

I think the original writer was refering to using LabVIEW to program ControlLogix 5000.  I am not aware of any software used to program the ControlLogix 5000 range other than Rockwell-Software RSLogix 5000.  I would use this in preference to any other software as it does support all four methods of programming the PLC.  I don't know of any other vendors selling ControlLogix programming software.

As far as communicating with the PLC once the code is running that is straight forward as others have said.  Use RSLinx Gateway and the OLE for Process Control (OPC) interface if you have several clients wanting to pull data or control the PLC.  Not I said Gateway version as other RSLinx versions do not allow OPC connections from other clients!

There are however several issues relating to the PLC data types that are presented to the OPC client (LabVIEW).  Booleans in the PLC are presented to the OPC client as a 16-bit integer (I16) with a value of either 0 or FFFF.  When displaying Booleans in LabVIEW you will need either to convert the I16 to boolean using a not equal to zero or using shared variables address a boolean SV to an I16 SV pointing to the OPC item.  LabVIEW does not appear to handle the OPC Id 5000 "Is Item Boolean" and some OPC Explorers handle this automatically. 

There are also other inconsistencies with LabVIEW 8.2 when reading data types.  In some browsing functions (cannot remember which one!) data types are incorrectly stated as DBL when they are I16!  If this really matters I'll look.

Lastly I have had speed of response issues when running RSLinx and LV DSC 8.2 on the same computer.  The poor response ranged from 2s to 14s!  Run RSLinx Gateway on a simple dedicated PC and connect with a higher performance PC running LV DSC via OPC.

I am experienced in ControlLogix PLCs and a "beginner" with LabVIEW!  Good luck.

Regards...Andy