AB7670 - Slow scan time 300-400ms +


Hi Johan,

Please let me know what you have tried and I will see what we can find out.

Thank you!


Serial a03f2c75


Hi Kyle this is what I have tried so far

PLC 1 (real PLC) Siemens PLC TIA V15 (CPU1513F)

Hardware setup

Tried change Update time , Set manually , same response

Tried different size of IN / OUT and Tried move Output and Input (swap places)

Tried send data with command write data to Profinet IO device and also direct from Hardware IOs , same results

Data tests over to other PLC 2

Function send signal out and need it back inside time limit normally we have 200ms , but this is not possible with this unit)


Print screen of signal back and forward between 2 PLC (real PLCs) (498ms long…)

Scan time internal PLC1

PLC 2 (other system side own PLC (Siemens S7 Classic)

Mirror signal from PLC1 direct back to PLC1

Scan time Internal PLC 2 (only have OB1 block everything else empty)

So only thing I trying to do is send 1 bit PLC1 over Ethernet Master (AB7670), into Ethernet Slave (AB7649) into PLC2 and return…

And response time is 200-500ms not constant, pretty bad

I really need some support what I can do or what’s going on

Best Regards,


Hi Johan,

Kristoffer wanted me to ask you:

Have you considered the default Update Rate of 100ms in respective direction and on top of that the throughput time of respective gateway and direction?
Depending on when the data is updated in that regards a one way may be as long as 120ms (just an estimate) or down to 20-30ms (10-15ms throughput), then the turnaround time in the plc and the same numbers back again…

He also suggested taking some packet captures with wireshark to see what is happening on the network. Do you want to try that?



I tried different update rate like I stated in my email same results only thing on network is hms gateway ab7670 and the slave Ethernet

So don’t think update is issue

I can try wire-shark

Still think it sounds way to long response time



What should next step be ? I HMS not interested to solve this ? do I need to escalade inside my company?



Did you find anything with Wireshark? We absolutely want to help you solve this, but I think my colleagues in Sweden are best equipped to solve this particular issue. Is it OK if I ask them to call in the morning?



Please ask them to call me tomorrow thanks for your support Kyle



EthernetIP wireshark info

And Profinet wireshark info file

Don’t know what I looking for maybe you guys can see something


Best Regards,


Hi Kyle have not heard anything more about this issue

Here is a print screen of same setup as your AB767 to and from same PLCs but with a old PN-PN coupler (v3.0)

Longest 27ms


Best Regards,


Sorry for the delay on this…

Am I understanding correctly that you trying to measure the time to write from PLC1 to PLC2 going through the AB7670 and the AB7649 and then get a response back in PLC1?

The packet captures look like they were only capturing broadcast traffic. You would need to mirror a port on a managed switch to capture everything. If you aren’t able to do that, can you send me the Anybus config files and scan list?

Sweden did not have much time to help with this today, but they are going to get me info in the morning on changing the data rate in the scanner itself, so I am hoping that will help with your case.



OK, so he was talking about the data rate from the scan list. Have you changed that?


Scan list for Ethernet/IP for allen Bradley , don’t know how to give you scan list from anybus?

Attached is X-Gateway files for both Master and Slave HMS Gateways


EtherNet.zip (630 Bytes)

A20163_EthernetScannerConfig.zip (1.57 KB)

A20163_LTA_EthernetSlaveConfig.zip (2.29 KB)


Sorry here it is MASTER AB7670



How do you change that I have no idea were to change that value_?

Can you support me to find out ?

Best Regards,


Have been looking everywhere to set any data rate I cannot find other than inside my Siemens PLC program that we talked about earlier.

Best Regards,


You can change it in the Anybus web server. See section 4.2 here:


Oh complete forgot that setting will change and try thank you for your support Kyle very appreciated



Kyle it worked to get scan time down to more normal ones forgot that setting in the scan list (

Excellent support from HMS

Thank YOU


Best Regards,


Excellent! Sorry it took a while to find the cause, I overlooked it also.

Thanks for your patience!