Reply To: Panelview Legacy HMIs dropping connections

EirelandEd Ireland
Karma: 16
Rank: Padawan

Thank you Ken S and Mister Incedible for your responses.

I should have mentioned in my initial post that the failing HMIs and PLCs are spread across three separate switches.  The 2960 that was mentioned connected three of the five failing legacy Panelviews to the network.

As a test, today I “shut” the port on the core switch that I had trunked the new C3560 switch into.   For whatever reason, this resolved the problem that the legacy Panelview (built with Panelbuilder32) HMIs had with dropping PLC connections.  Several tests were run to make sure that this wasn’t some sort of fluke;  as long as the C3560 was disconnected from the core, the HMIs had no trouble staying connected,  but after reconnecting the C3560 the HMIs would drop the PLCs within 35 minutes.  Leaving the C3560 disconnected from the network wasn’t a long term fix as it is used to tie a VMWare cluster and a SAN to the network that provide essential services.  Excluding VLAN30 in the trunk configuration between the core and the C3560 appears to be a satisfactory solution until we can either upgrade the HMIs to a newer (supported) version or figure out what the real problem is.