1768-ENBT safety controller losing communication when pinging

[EExcitement 0]

Hi,

I work at decent sized factory with a lot of automation and we have a few of these 1768s with the L43S safety PLC that faults out when an external source pings them usually RSLogix. I'm assuming it's the safety plc, because all of the safety gates will be flashing the open request and the main HMI will say emergency stop has been pressed. We have 4 of these cells that have these PLCs and will do it on random. I did notice on one laptop that i did not have RSLogix 5000 but studio 5000 it would fault out one or two of these cells everytime i would scan the network with the EthernetIP driver. Once i had installed RSLogix 5000 this problem quit happening. Here recently it is happening again but no idea how. We think our new network manager has something to do with it and randomly pings all our devices. Is there a setting or something in these PLCs that is recognizing external pings and faulting out the PLC? someone please help!

[BobLfoot 301]

I don't suspect it your pinging them perse that is causing the fault, but the effect it has on connections and timing.  A few things to check.

1.  Goto the PLC's webpage and check for communication issues like dropped packets and retries.  While there also pay attention to the connection count.  If it is at or close to limit this can cause problems.

2.  Check and make sure you're using intelligent switches as the top level of each cell and keeping that cell's traffic to itself.  Cross Cell traffic can cause retries.

Just a couple quick things I can think of..