Domoticz + PLC Simens LOGO - Is there a possibility

[Daro1003]

Hello,
Is it possible for Domoticz to communicate with a Siemens LOGO PLC? If not, can Domoticz easily communicate with another PLC?
If it's possible with Siemens LOGO, how do I do it? I happen to have a Siemens LOGO in stock.

I'm asking because I'd like to implement lighting automation, and on the LOGO PLC, it turns out to be just a few blocks and works flawlessly. However, Domoticz has a script called dzVwents, which doesn't always work properly – it doesn't always turn off the lights, and the switch doesn't always work as intended.
I'm testing it on a PLC, and it works very well. In this case, Domoticz would function as a remote control, as well as control from Dashticz control panels.

[waltervl]

Domoticz is always a remote system for controlling hardware as it is software. There will always be an interface. The better the interface and hardware protocol, the better it will work.
I prefer zigbee (wireless and safe) but others prefer something else.

I am not aware of a Logo PLC integration but did not Google for it (you probably did that already).

Edit, also check the forum search: search.php?keywords=siemens+logo

[Daro1003]

Unfortunately, I'm having the same issue: using the plugin in question causes Domoticz to freeze and stop. I can't even edit the plugin settings because Domoticz freezes.

There must be another way, since Siemens Logo supports Modbus communication, so perhaps NodeRed will help?
@FireWizard is an expert on the subject, so maybe he can help.

[FireWizard]

Hello @Daro1003,

Sure we can help, but it will depend on which Logo PLC you have.
NR has an example for the Logo 8.
See; https://flows.nodered.org/flow/f36b5e6e ... eb45cbad0d

As far as I can see, it uses the S7 protocol.

Let me know,

Regards

[Daro1003]

My Logo is OBA8 and here is the exact model:

IMG_1822.JPEG (399.85 KiB) Viewed 190 times

If there is another model that can be communicated, I will buy another model because I noticed useful functions in the logo that I can use in my automation.

After logging in to Logo, I found the following data in the Logo Soft Comfort program:

DaneModbus.jpg (62.49 KiB) Viewed 189 times

[FireWizard]

Hello @Daro1002,

I do not own a Logo PLC (like the Shelly 2PM, when developing those other flows), so testing, etc. has to be done by yourself.

However, I noticed, that a simulation program for the Siemens Logo PLC exist, but I have not been able to download it, yet.
Have to look for a Linux version.

But for now:

Follow the description, that you will find at: https://flows.nodered.org/flow/272a6d21 ... 1bae025ead.

Try, if you can make a connection with your Logo8 PLC

Regards

[Daro1003]

Spróbuj, jeśli możesz nawiązać połączenie ze swoim Logo8 PLC

It seems the connection was successful:

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Now how to view outputs and inputs and be able to control them from domoticz.

[Daro1003]

The connection seems to be working because I've added four outputs, Q 1 - 4. There's just something strange going on. When I physically violate the input on the LOGO that activates OUT 1, the state of all the blocks in NodeRed changes from false to true – so something isn't working properly.

There are some errors in red on the sidebar.

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[FireWizard]

Hello @Daro1003,

That is an important fist step, that Node-RED is able to communicate with ypur Logo9 PLC

You can try now to load the example from: https://flows.nodered.org/flow/f36b5e6e ... eb45cbad0d

Test this and see if this functions. Do not forget to change the configuration, if they are different.

In the meantime I will try to find a demo-tool, to install on my PC.

Some YouTube video's also exist, e.g. https://www.youtube.com/watch?v=rZ3fDlhDkv0
and this one: https://www.youtube.com/watch?v=3rvBKl6I524

Try to replicate this in your machine.

Regards

[FireWizard]

Hello @Daro1003,

I have been able to find, download and install the Logo! Comfort Software version 8.4
It is a nice program, to play with, but unfortunately, I think, the demo version cannot connect to Ethernet (is greyed out).
So I cannot connect my Node-RED to that Demo program. You have probably a licensed version.

So all the testing has to be done by yourself.
But we can try.

Regards

[Daro1003]

I don't think it's realistic to connect it to Domoticz.

I tried both videos - in the first one, I have slightly different options in the nodeRed blocks.

In the film:

w filmie.jpg (56.39 KiB) Viewed 110 times

At my place

uMnie.jpg (45.03 KiB) Viewed 110 times

In the second video, it works fine, but it's only the input state. So, when I click IN on the controller, the state only changes for the duration of the click. We want to see the relay's state and also be able to control it from Domoticz.

I don't know if this is a realistic connection.

The question is, what exactly do I need to achieve?
I understand that:
In Node Red, I need to see the status of the relay on the LOGO, and I need to control the relay on the Logo from Node Red.

[Daro1003]

Hello, after a long time - this thread has started.
Currently, I have two Siemens LOGO PLCs at home connected to the LAN and controlled by Domoticz via NodeRed.
Everything works well and stably.

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The flow created with ChatGPT took several days of testing, failures, and doubts, but it finally worked, and everything works perfectly.
I'm attaching the entire flow for my colleagues to review and to see if it might be useful to someone else.
I think a PLC is an excellent lighting controller – stable, resistant to interference, etc., and, after all, used in industry.

Domoticz - SiemensLOGO.txt

(9.29 KiB) Not downloaded yet