CompactLogix L24ER to Kinetix 300

[CRom11]

Hi,

any help would be greatly appreciated as I'm stuck..

I'm working on a system with 1769-L24ER (v21), 4 powerflex 4 drives and KInetix 300(v1.81). In local panel they are connected to a AB switch, not sure but I think its Startix 2000 but not 100% sure. When the system is not connected to the factory network all is fine, when I connect the ethernet wire to factory network first thing I notice that all port led lights on the factory switch (Cisco not sure of model) will start flashing with same frequency and after an hour or so I get random comms issue around the factory. Managed to narrow it down to the Kinetix300, if this one is unplugged all works fine.
I tried using the Unicast connection but that always times out and doesn't want to work. That was done on rockwell tech support advice, upgrade the PLC rev to 21 and servo to latest FW, all done but same issue.

Would anybody have an idea what to try next?

Many thanks,

Jan

 

[thelinuxman]

I hate to ask the obvious, but did you make sure there is not another device on the network with the same IP address as the Kinetix?

 

[CRom11]

Hi, yes we did, one of the first things we checked. What strikes me is that on the cisco switch all led light indicating port activity will start flashing with same frequency, haven't seen this before.

 

[Ken Roach]

What you're seeing is almost certainly UDP Multicast traffic that isn't being constrained by managed switches.

A quick check with Wireshark on any of the managed switch ports will show that traffic at the cyclic rate defined by the connection to the Kinetix 300.

So you've got two approaches: configure the enterprise network to properly use IGMP Snooping and IGMP Querying to constrain mulitcast traffic, or pursue troubleshooting why the Unicast connection to the Kinetix 300 isn't working.

 

[CRom11]

Thank you, I'll speak to our IT (pain in the.. ) about limiting the traffic on that port. I couldn't prove it but I though the led flashing would be something to do with the Kinetix update rate.
Any suggestions why the unicast wouldn't work? When spoken to rockwell tech support all they told me was to update compactlogix to v21 and Kinetix to v1.81, still no joy, do not know what to try next..

 

[Ken Roach]

I found a couple of articles in the RA Knowledgebase that suggest that the Kinetix 300 only supports multicast connections.

 

[CRom11]

If I understand the '461215 - Kinetix 300 Ethernet Protocol' knowledgebase article broadcast only works for implicit messages, for explicit all connections are available.

Other thing I just noticed and don't know the difference:
Properties on the Kinetix in RSLogix5000, General tab: EtherNet address section has 3 options: Private network, IP address and Host name, I have the IP address chosen, but looking at the programming example they have the Private network option selected. What is this for?

 

[Ken Roach]

The types of networks are just for convenience in entering and managing the IP addresses. It would work just the same on an Automatic Private IP network as it does on an ordinary Class C subnet like 192.168.1.xxx.

The Knowledgebase document you cited sounds a little defensive, but it boils down to "The Kinetix 300 supports multicast I/O connections only, and there's nothing wrong with that".

So your only choice is to isolate the network containing the Kinetix 300 from the enterprise network, or get the various connected network switches properly configured for IGMP Snooping and IGMP Querying.

 

[CRom11]

Thanks, really sounds like this would be my only option as tech support have been useless in helping me they response is 'we don't know what is on your network and there's no reason why a Kinetix 300 should bring your network down' that's as much help as I got from them.
Right, will to try to justify purchasing managed Stratix switch and will see how I get on