Enet IP communication with 1794-AENT module

[gyachts]

Has anyone had success with communicating with the Rockwell 1794-AENT/B ethernet modules?  I have one of the Flex I/O ethernet interface modules with two 8 port analog in modules connected.  I can read the 1794/AENT module information, using the ENET-I/P library, like model, version etc but nothing representing the I/O data. Greg CVC

Kudos! Thanks!

[Adam G]

Hello Greg,

I was wondering how you are communicating with your device. Are you using LabVIEW, CVI, NI-VISA commands? This would help us try and figure out how to successfully communicate with your device. Have a great day! 

Best Regards,

Adam G

[gyachts]

Adam, I am using Labview 8.6 with the EtherNet-IP library.  I have a ethernet connection to the 1749-AENT/B module and that is woring and tested.  Attached to the 1749-AENT/B interface is a 1749-IE8K 8 port analog input module.

I am able to read the attributes from the 1794-AENT/B module using the Ethernet-I/P library's "EthernetIP CIP Get Attribute Single VI" function in Labview.  I get the name of the module, the major and minor versions, the type of module etc.  What I can’t seem to figure out is how to read the I/O data from the 1794-IE8K module attached to the 1749-AENT/B.  I'm trying to use the "EthernetIP Tag Read VI" function in the same library.  It might be that I just don’t know what the “Tag Names” are supposed to be.I’m using an Ethernet-IP “EthernetIP Tag Read VI” function from the Labview library that is wanting several variables.  The network path is the IP address of the module and I know that’s right.  Also asking for a “Tag name” and number of elements.  These two I’m not sure about, maybe one of your guys can help me with what the Tag name should be and how many elements there should be.  Also I can select the type of data out which can be an SINT, DINT, INT, BOOL, STRING, RAW or REAL.  I’m assuming INT or DINT then scale. Thanks for the help.  Greg Yotz

CVC

[Adam G]

Hi Greg,

Since you are using a product released by NI Labs you are going to be able to get the best support by posting on their discussion forums. They have the most knowledge about the library and will be able to provide the best support. Have a great day!

 Best Regards,

Adam G

[Viejo]

We are now facing a similar situation; we need to use LookOut to communicate with an Allen Bradley Rockwell 1794-ACNR15 I/O connected to a series of modules, mostly for RTDs

[Ryan.S]

What's your lookout version? If it's Lookout 6.2 or later, you can use NI OPC Server to connect it.

[gyachts]

I talked to several people at NI and we never came up with a solution for the ethernet connected Enet IP - Flex I/O we were using.  Turns out the I/O modules on Flex I/O buses need information loaded into them before they can be used and it was out of our scope for the project.  I ended up using a small compact logix PLC with support for Enet IP to communicate with all 3 locations and it acted like a data concentrator.  It also held calibration data in it that was applied to all readings.  The cost of the Compact Logix PLC was much lower than the man hours it would take to get a NI or third party solution to work reading from the modules directly.

With Labview it was very easy to implement reading the tags from the PLC that held the information from the Flex IO.

Greg Yotz

Control Vision Corp

[Viejo]

Thank you Greg, I suspected that it could not be done "cleanly"

[gyachts]

I think if you had time you could sniff what RSNetworx or RSLinx sent and reverse engineer it.  For our project I was constrained for time and money, so the ~$2000 for the PLC was much cheaper then the engineering time to figure out what was being pushed into the IO modules to configure them.  I know the data is based on the information in the EDS files for the modules plus some configuration stuff but that is as far as I went.

I did find a couple companies that were working on or had software libraries or modules to do it but they either were too expensive for my project or weren't ready for release.

Greg