Use a PLC to Program External Instruments via Ethernet?

Hi all,

I am using a Compact Logix 1769-L33ER PLC with RS Studio and Factory Talk View software to develop a protection and control system. In addition to monitoring other protection systems, it uses several pieces of programmable Test Equipment (Oscilloscope, DMM, Power Supplies, etc.) that are remote controllable via Ethernet.

Is there any way anyone can think of to use the PLC to send and receive Ethernet SCPI Command language messages? For example send "SET VOLT 5.0 SET CURL 2.5 SET OUTPUT ON" to Ethernet IP address 192.161.1.100. I can't find any Ethernet software library interfaces. Any alternative approach ideas?

Many thanks to all for donating your time and wisdom. Cheers!

Tim

<< crickets chirping >>

Anyone?

I believe Logix can only communicate with AB processors or devices that have CIP connections. There is no generic type message instruction with Ethernet. The only generic type messages from a Logix is thru the serial port. So if you could find something to go from serial to Ethernet you may be able to do some custom type code to communicate to those devices. You may want to checkout interfaces like Profibus, Modbus and CAN all of which you can get cards for the Logix. There is also devices like the Red Lion DSP which has multiple protocols (they may have a custom one you can make) and lets you map one device to another.

The communications bridges from Red Lion and others should do the trick, with appropriate message instructions in the PLC program.

The 1769-L33 controller is one of the modern "5370" series CompactLogix that does support raw Ethernet socket services as well as the well-managed CIP protocol services that make messaging, I/O, and upload/download run.

It's not easy to use; you need to execute multiple encoded MSG instructions to configure the socket, open the connection, and send the data.

There is an application programming manual for these functions, ENET-AT002 (direct link to PDF)

I like the recommendation of the Red Lion DataStation Plus or G3 HMI for this sort of communication gateway function. The PortPrint() and PortPrintEx() instructions in their C-like language are much easier than configuring MSG instructions in the CompactLogix.

There was a discussion a couple of years ago about a programmer doing a similar SCPI protocol interface with a Red Lion, and the challenges and workarounds they encountered: Link

Thanks guys, these are much appreciated good suggestions. I will definitely look into the Red Lion solution.
Tim

Just got this from AB tech support today. Looks like Prosoft may have a new solution now as well.

Industrial automation applications consist of a variety of devices. Oftentimes, you will find that the devices you are using do not have a CIP interface. Join us on Tuesday, June 16th at noon United States Eastern Standard Time to learn how to integrate non-CIP devices into your Rockwell Automation control architecture. Chris Hines, Product Manager at Prosoft Technology, a Rockwell Automation Encompass Partner will discuss the steps necessary when working with non-CIP devices in order to increase productivity and efficiency in your control system application.