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EtherCAT capture - Printable Version

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EtherCAT capture - DaveBarnett - 05-08-2019

The screen capture attached here was from traffic between my CK3E and several ECAT servo drives, everything working normally, and with clock rate of 1KHz. I see the broadcast packets at the 1 KHz rate (0.0009999 delta) ...but can anyone tell me what the less frequent packets of length 64 are ?

Thanks !

RE: EtherCAT capture - Eric Hotchkiss - 05-14-2019

Hi Dave,

It does look like the size 64 packets have a period of 10 ms. It's possible that they are from SDOs called either in a PLC or the watch window (if you lowered the default period). Maybe you have a 10 ms timer in a PLC. Try disabling PLCs are seeing if it goes away.

It is also possible that they could be from transfers to devices in freerun mode. Is this all Elmo drives or do you have any IO devices in your network?

RE: EtherCAT capture - DaveBarnett - 05-15-2019

Thanks, Eric. But, plcs running. And only 3 drives on the network. I'm wondering if this has something to do with distributed clock sync ??

RE: EtherCAT capture - Eric Hotchkiss - 05-15-2019

The only answer I was able to get was asynchronous maintenance packets and that if you did send SDOs they would most likely be in those packets.

I also want to point out that they have a period of 10 ms, where the larger ones had a period of 1 ms.