Hello,

I am using a Scalance x208pro and I have an repetitive error that I would like some help with.  

I was having random profinet errors that occurred daily that would cause my safety devices to passivate for lost frames that were pointing me to a scalance.(IO DEVICE FAILURE - NO frame received)  I found that each time we had the device failure, a different device would be passivated.  

I used the simatic net tool to discover that one of my ports were having hundreds of CRC alarms each minute.   This scalance switch was the common source for all devices faulting and they were communicating through the same port to the PLC.  

I replaced this scalance switch and I have had no more profinet errors in 2 weeks (io device failure - lost frames).  This was the solution to the IO device failure topic.  

However, i am now seeing 1 CRC alarm per minute vs. 100+ per minute.  My question is what can i use to determine what is causing these errors?  Wire shark cannot detect any CRC errors according to their website.  

Is it normal to see CRC errors on a port on the scalance?  If so, what is the amount that can occur before the errors start slowing down the network?  

Thank you,

Dustin 

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Split from Cyclic Redundancy Check (CRC) error on data message frame.

Hello,

CRC erros can be caused by cable, hardware or the chip of the scalance.

many  CRC errors can cause many network problems and it slows it really down.

If possible replace the cable on antother port, or else , replace the scalance.

In a MRP ring, the master still thinks the network is okay...