# Is a Siemens Open Controller compatible? **URL:** \ **Category:** Ignition\ **Created:** [November 1, 2017, 3:36pm UTC](https://forum.inductiveautomation.com/t/is-a-siemens-open-controller-compatible/15842 "2017-11-01T15:36:22Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![m.currier](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/m.currier/32/4238_2.png) [@m.currier](https://forum.inductiveautomation.com/u/m.currier)\ **Post date:** [November 1, 2017, 3:36pm UTC](https://forum.inductiveautomation.com/t/is-a-siemens-open-controller-compatible/15842/1 "2017-11-01T15:36:22Z")
We’re using a Siemens ET200 Open Controller which is basically a Windows 7 embedded system with a soft-PLC & I/O grafted in. The PLC runs on the same hardware but on a different subnet than Windows. The PLC runs its own OPC UA server. After installing Ignition the PLC/HMI comms stopped working. Also, I never could get Ignition to connect with the soft-PLC or the OPC UA server on the PLC. I tried changing ports, changing IPs, adding secondary IPs, turning SSL on/off, regular & edge versions, and [of course] rebooting ad nauseum. I was able to connect to both the PLC and the OPC UA server from another PC running Ignition (and setup EAM). Uninstalling Ignition fixes the HMI comms problem but then I can’t have Ignition :P. I’d love to have some direction in troubleshooting the issue(s). Thanks in advance for you help. ---
**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\ **Post date:** [November 1, 2017, 3:38pm UTC](https://forum.inductiveautomation.com/t/is-a-siemens-open-controller-compatible/15842/2 "2017-11-01T15:38:39Z")
You should certainly be able to connect to the onboard OPC UA server. I assume the Siemens driver works as well and the reason the HMI comms stopped working is that there’s a limit to the number of S7 connections the controller can have active. What kind of error messages did you get when trying to connect via OPC UA? ---
**Author:** ![m.currier](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/m.currier/32/4238_2.png) [@m.currier](https://forum.inductiveautomation.com/u/m.currier)\ **Post date:** [November 1, 2017, 4:33pm UTC](https://forum.inductiveautomation.com/t/is-a-siemens-open-controller-compatible/15842/3 "2017-11-01T16:33:33Z")
Thank you. Removing the direct device connection fixed the HMI comms issue. Trying to _Discover_ the OPC UA endpoint yields this: Error: io.netty.channel.ConnectTimeoutException: connection timed out: /192.168.0.1:4840 ---
**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\ **Post date:** [November 1, 2017, 4:41pm UTC](https://forum.inductiveautomation.com/t/is-a-siemens-open-controller-compatible/15842/4 "2017-11-01T16:41:51Z")
Are you sure that’s the right IP address? Is the OPC UA server enabled? You’re sure there is one? ---
**Author:** ![m.currier](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/m.currier/32/4238_2.png) [@m.currier](https://forum.inductiveautomation.com/u/m.currier)\ **Post date:** [November 1, 2017, 4:47pm UTC](https://forum.inductiveautomation.com/t/is-a-siemens-open-controller-compatible/15842/5 "2017-11-01T16:47:33Z")
The full URL is: opc.tcp://192.168.0.1:4840 I can connect to this from Ignition on my laptop… ---
**Author:** ![m.currier](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/m.currier/32/4238_2.png) [@m.currier](https://forum.inductiveautomation.com/u/m.currier)\ **Post date:** [November 1, 2017, 8:01pm UTC](https://forum.inductiveautomation.com/t/is-a-siemens-open-controller-compatible/15842/6 "2017-11-01T20:01:44Z")
I have further tried disabling Windows firewall and changing the port number…to no avail. I can still connect from a remote Gateway but not the Gateway on the same machine… ---
**Author:** ![chaoliang](https://avatars.discourse-cdn.com/v4/letter/c/ba8739/32.png) [@chaoliang](https://forum.inductiveautomation.com/u/chaoliang)\ **Post date:** [July 11, 2023, 1:47am UTC](https://forum.inductiveautomation.com/t/is-a-siemens-open-controller-compatible/15842/7 "2023-07-11T01:47:46Z")
Hi, just to follow up whether you have it resolved? How's the performance of ignition running the open controller?