Connection retries

[dwilkins]

We turn off power to our PLC's every night then back on again the next morning.   I've noticed that most days my Advanced HMI app reconnects fine on its own with no extra code by me but some days, especially after two day weekends,   the PC quits sending packets to the PLC and HMI gives "No Response" when reading. 
How does the retry mechanism work in HMI and when it quits sending packets, is that the Windows network stack or the HMI code? 

[Archie]

Which driver are you using? The CLX drivers usually get the most extensive testing for loss of communications, but the others should work just as well.

[dwilkins]

Micro800

[Archie]

The Micro800 driver is the same driver as the CLX driver. When it stops communicating, can you run a Wireshark packet capture to see if AdvancedHMI is making any attempts to reconnect?

[bachphi]

In my previous job, I set PCs reboot weekly on Monday morning before the A shift start in Task Scheduler.   

[Archie]

I forgot to ask which version of AdvancedHMI you are using?

[dwilkins]

Wireshark shows no traffic from AdvancedHMI.   Using version 399r.

[Archie]

I tried to replicate this many times by disconnecting the Ethernet, but every time it re-established communications. I will setup a test and let it run for a couple days.

[dwilkins]

What was the outcome of your extended testing? 

[Archie]

I started up an HMI, then disconnected the cable and left it like that for over 12 hours. I then reconnected the cable and within a few seconds it started communicating again. This was using the latest version of 3.99s

So unfortunately I have not been able to replicate it yet. After the holidays I can try more tests over longer periods of time.

[ed288]

Hello.

I'm using SLC 5/05 with EthernetIPforSLCMicroCom driver, the applications are installed on a server that is dedicated to keep records of the production and PLC's are only turned off on weekends.

What happened is that after a long weekend the applications loose communication with the PLC, at this time i have 3 apps that are connected to 3 different PLC and all did the same this weekend. After i restart the application all worked fine. But i have not found what is causing this.

I think that was a network issue or a problem with the database but after i read this thread i knew that is the same problem that i have.

On server i have another app that keeps record of the temperature and was developed before i found AdvancedHMI, this app use RsLinx OPC Server to communicate with PLC and is not failing to reconnect to the same PLC after a long weekend.

I try to found something that keeps connection alive on code wtih no luck.

Thanks for all the help you can give to us.

[Archie]

I've been doing quite a bit of testing with version 3.99s and so far I have been unable to replicate this. I'm going to leave the PLC off for 4 days, then see it AdvancedHMI reconnects after powering it back up.

[Archie]

Good news is that I was finally able to replicate this problem. It will be fixed in upcoming version 3.99t

[ed288]

Thanks for the support Archie, wait anxious for the next release.

[bachphi]

Good news is that I was finally able to replicate this problem. It will be fixed in upcoming version 3.99t

Very good news , indeed!!!!!!!!!