Micrologix 1400 to Watlow PM-6 Ethernet CIP

[unsunghippie]

Hello all,

I have been attempting on and off for over a week to read the temperature out of a Watlow PM-6 to a Micrologix 1400 over ethernet. I will start by saying I am not well versed in ethernet CIP, however I can read an addressing chart and have made it work with AMCI and Emerson drives in the past. The Watlow is supportive of explicit communication (according to the manual).

Facts:

-PLC is at address 192.168.1.108
-Watlow #1 is at 192.168.1.121
-all subnet masks at 255.255.255.0
-I can successfully ping both from PC
-RSlinx recognizes Watlow on network
-connection light on Watlow flashes (no connection) but link light is lit solid
-There is 1 AMCI drive and a Maple PLC also on the Micro 1400 ethernet working fine.


I have tried in my MSG block "get member" 0x77,2,1 (class, instace attribute), "get attribute single" 0x68,1,1, and get assembly 0x77, all per the Watlow manual using the appropriate size of read bytes. I have also downloaded a program that does absolutely nothing other than try to get temperature and disconnected the HMI so only the Micro, Watlow and my PC are on the network, same error.

Mutihop in the Micro 1400 was set to 192.168.1.121 for all the above.

I have tried code that was sent to me for a SLC 5/05 with a MSG block that read the Watlow as a PLC-5, to no avail(the blocks are a little different RIX file vs. control block).

In every instance I have tried, my MSG block returns Error Code (hex): d6, Connection timed out by network. At this point I would be excited to get a different error code.

I have been through Google, manuals, another Watlow PM-6, and Watlow tech support to no avail (although they have seen it work).

Has anyone made this combo work? MSG block post? I am open to any ideas.

Thanks in advance.

 

[Ken Roach]

Post a link to the Watlow EtherNet/IP user manual. With so many different mechanisms (Assembly, CIP Object, PCCC emulation), you would think one of them would work.

At this point a protocol analyzer, in particular the terrific free Wireshark, is going to help a lot.

If you have an Ethernet hub or a switch with a mirror-port function you can listen to the traffic between the MicroLogix and the Watlow device. I use my USB Ethernet tap from Frontline Test Equipment for this sort of thing, but any managed switch will work. A cheap alternative is a dedicated-purpose small mirroring switch from DualComm.

If you have a licensed version of RSLinx Classic, try making an OPC connection to one of these CIP objects. If that works, you can watch the traffic directly in Wireshark.

To create a direct CIP object reference in RSLinx, create an OPC topic pointed to the device and use the syntax:

[Topicname]<class>:<instance>:<attribute>[MemberNumber],<type descriptor>

For your example, it would be [Topicname]102:1:1,u16

 

[unsunghippie]

Watlow Ethernet/IP user manual. Good one! Closest I can get is:

http://www.watlow.com/downloads/en/manuals/ez-pmi-revj.pdf


Wireshark, interesting. Never used it. I am only Lite linx here. I don't maintain a higher license on hand, but have done several OPC projects for customers, if it comes to that.

 

[unsunghippie]

More info

Once again no Ethernet/IP expert here, but getting slightly closer.

After spending some time at the Watlow factory, the following has been determined: (via Wireshark and people who know more than me.)

The Micro 1400 is attempting to establish connected explicit communication.

The ethernet card firmware in the PM-6 (as openly stated at Watlow) does not support connected explicit communication only unconnected explicit communication.

The facts established along with the facts posted before which have not changed lead me to the following questions, for which I will appreciate any input:

Is there a way via MSG,RIX,system to force the Micro 1400 to unconnected explicit comms on Port 1?

I found the following doc: (BTW I love the title of, now I can write I Recommend You Send Me a Million Dollars.)

Section 4.2.2
http://www.odva.org/Portals/0/Libra...Functionality_for_EtherNetIP_Devices_v2.0.pdf

Being a recommendation, does ODVA have any teeth? Do they require cert tests or anything, or are they truely just a recommendation?

If compliance with ODVA is required, or even strongly encouraged, shouldn't both devices support both forms of comm?

Am I completely out to lunch?

edit: And as far as them having seen it work in my original post, yep me to, at their factory, on unperfected ethernet card firmware, sometimes.