Cannot connect to Siemens HMI


I have reviewed all posts in the past related to connection to Siemens HMI through Flexy 205 and Talk2m VPN unfortunately none of them can solve my case.

Here is the description of the case:
(1) I am able to ping/go online/download to the PLC connected to LAN of Flexy205 (S7-1200)
(2) I am able to Ping HMI connected to LAN of Flexy205 (KTP-900)
(3) Both PLC and HMI are added as LAN device of the Ewon gateway on eCatcher
(4) The messaging forward tag “BroadcastForwarder” was set to “1”

What I mean by connection failure to HMI is that I can neither download or go online in TIA V16 software. The IP address of the HMI was inputted in the TIA V16 software and TAP-Windows Adaptor V9 was selected as the PG/PC interface based on the last post from this discussion (EWON commmunication with Siemens HMI-TIA Portal v16 - #7 by MichaelHabashy).

Here is a snapshot of the searching screen.

Thank you for your assistance,

Can you ping the HMI?

Can you send a backup of the Ewon taken with eBuddy and including the Support files?

What is the model of the HMI?

I will need to know the model of the HMI to see if we have any information about it.

You may need to check with Siemens to find out what type of connection is needed and if it is possible to connect with TIA Portal via a VPN connection or not.

Sorry for the late response. The problem occurs by a colleague in a different country so it takes a little time for me to get the update.

We are able to ping the HMI IP address. The HMI is KTP900 Basic (6AV2123-2JB03-0AX0). We were able to see the HMI screen live when smart@service function on the project and at the HMI screen were activated.

Right now the problem is frequent timeout issue which makes it impossible to download/upload HMI and PLC programs. We hypothesized that the issue may be caused by unstable connection since EWON is using wifi connection. The equipment is under shipping so I couldn’t provide any backup immediately. We will probably try it again on local hardware and see if we have the same timeout issue.

I would need to see the backup with support files to determine what the best steps are for resolving this issue. Please let me know when you are able to make one.

In the meantime, if you have the serial number for the device, I can look it up from our end to see if there is any indication of the issue. Where is the device located and where are you connecting from (geographically)?

The serial number is 2110-0549-24.
Device locates in China and my colleague was connecting from Germany.

We will provide a backup when the equipment is online again.

I agree that this is a likely issue. I can see that it’s going offline frequently, on average around 10 times per day. Sometimes it will stay online for a few hours, but other times it’s less than an hour. Once we get the backup with support files we’ll have a better idea of the reason.

However, even if the connection problem is fixed, I’m not sure if this HMI supports going online over the VPN. Have you tested it before shipping it out?

We were able to see the HMI screen live when smart@service function on the project and at the HMI screen were activated. We can connect with the Siemens smart client to program the HMI screen and mirror the screen to my computer. This is a basic panel so an additional license is required for this function.

So if that functionality worked over the VPN before you shipped it, it should work once the connection issue is resolved.