Have 2 1783-US16T Switches.Powerflex 525 stay connected but Panelview lose connection

Good Evening ,


I have a large machine that has 2 - Rockwell 1783-US16T unmanaged switches. I have about 17 Powerflex 525 drives that keep communication , but about every 10 minutes I lose communication to my 4 Panelview Plus HMI's. Replaced the cable , took the HMI Ethernet cables and moved over to the other 1783-US16T switch , and the same thing. I never seen anything like this before . This system has lasted for years and I can't imagine I have 2 bad 1783-US16T switches.


Have you seen anything like this before ?


Thanks so much in advance .

HMI's and Drives/IO all on the same network?
Start by looking at the Ethernet module directly, and check it's error rate and connection count. Just someone throwing in a MSG instruction will bump up the Connection Count, and running out of them is bad.


I'd say also look at the error tables on the Switches themselves, but they are so slow to load and update, it is frustrating.

rdrast said:

HMI's and Drives/IO all on the same network?
Start by looking at the Ethernet module directly, and check it's error rate and connection count. Just someone throwing in a MSG instruction will bump up the Connection Count, and running out of them is bad.


I'd say also look at the error tables on the Switches themselves, but they are so slow to load and update, it is frustrating.

Click to expand...

Do those switches even have error tables? I haven't used the Stratix 2000s but I thought they were unmanaged and didn't have that feature.

What processor/communication adapter are you using and have you added any additional messages lately? Sounds like you could be running out of connections on your processor. 17 drives and 4 HMIs is a large number of connections on some processor or communication adapters. Usually you can check that on the webpage for the device.

Ok. So I connect to my CompactLogix L33ER , Internet Explorer , type in the CompactLogix IP Address , and I will get the processors webpage ?

I just don't know what could of happened different . It has been in for 2 years,
same connections , same devices , no program changes , not a hint of issues in 2 years , etc.

Any particular things I can change in the L33ER , to allow a greater number of devices ?

Thanks so much in advance .

Take a look at the CIP connections and CIP connection statistics

This sample is on my workbench with no connections, but it will tell you the current and max for each type

Good Morning ,

I wanted to give you guys an update . I think I narrowed it down to one Ethernet cable . If you could educate me a little about networking , if you have a bad Ethernet cable , but you still have it plugged in the Ethernet switch , but not the HMI , can it still crash your network ? What happens in a ethernet network if you have a bad Ethernet cable with wires touching ? Can that cause your network
to crash , or would it internally just turn that port off on a unmanaged Stratix switch ? What issues would a lot of “ crosstalk “ do ?

Thanks for all your help .