Send data from iot device to HMI through azure iot hub using mqtt protocol.

Question

Send data from iot device to HMI through azure iot hub using mqtt protocol.

Konstantinos Krikelis 0

Hello, I am trying to send data from an industrial router to a HMI (Scada) system. So far, I am sending messages from the router to Azure IoT Hub. But I am confused on how to subscribe to them from the HMI.

LeelaRajeshSayana-MSFT 17,766 Reputation points Moderator

2023-05-30T14:24:48.5366667+00:00

@Konstantinos Krikelis Greetings! I am following up to see if you got a chance to review the below response. Please let us know if you have any additional questions or need further assistance. If the response helped, please do click Accept Answer and Yes for the answer provided. Doing so would help other community members with similar issue identify the solution. I highly appreciate your contribution to the community.

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LeelaRajeshSayana-MSFT 17,766 Reputation points Moderator

2023-05-30T14:24:48.5366667+00:00

@Konstantinos Krikelis Greetings! I am following up to see if you got a chance to review the below response. Please let us know if you have any additional questions or need further assistance. If the response helped, please do click Accept Answer and Yes for the answer provided. Doing so would help other community members with similar issue identify the solution. I highly appreciate your contribution to the community.

Answer 1

Sander van de Velde | MVP 36,761 MVP Volunteer Moderator

Hello @Konstantinos Krikelis,

the Azure IoT Hub is perfect for sending data to the cloud and optionally sending commands back for a full control loop.

I'm not sure where the HMI is living, but I expect this is some solution in the cloud.

Then you want:

industrial router -> Azure IoT Hub -> [something] -> HMI

It's not clear from what you share how data is provided to the HMI.

If the HMI can read data from databases eg. Sql Server or Azure Data Explorer (just like Grafana) then you need to persist the incoming data in that database:

industrial router -> Azure IoT Hub -> Azure Stream Analytics|Azure Function -> DB <- HMI

But perhaps your HMI can ingest streaming data (like using a REST endpoint or MQTT endpoint).

In that case, you need to call the endpoint for each incoming message.

An Azure Function is most convenient:

industrial router -> Azure IoT Hub -> Azur function -> HMI endpoint -> HMI

An alternative is using an HMI in the local network.

In that case, why should you use the IoT Hub between the router and HMI?

How about using an edge solution.

Here is an example of using Azure IoT Edge for local logic.

If the response helped, do "Accept Answer". If it doesn't work, please let us know the progress. All community members with similar issues will benefit by doing so. Your contribution is highly appreciated.

Konstantinos Krikelis 0 Reputation points

2023-05-23T06:25:43.82+00:00

Hello @Sander van de Velde | MVP ,

Thanks for the kind reply.

The router and the HMI are not in the same local network. That is why I opt sending data to Azure Cloud and then send them to the HMI.

So far, I did configure the router as a new device in the IoT Hub and it works fine. I can send data and then monitor them from the Azure IoT Explorer.

My HMI on the other side has MQTT interface and the parameters I need to configure are the following:

-Hub Name

-Device ID

-SAS Token

-CA certificate

-TLS Version (I normaly use tls v1.0)

Could you please assist me in the configuration?
Konstantinos Krikelis 0 Reputation points

2023-05-23T07:29:37.6+00:00

Also can you please tell me If I have to add the HMI as a new device in the IoT Hub?
Sander van de Velde | MVP 36,761 Reputation points MVP Volunteer Moderator

2023-05-23T08:39:03.27+00:00
Hello,

yes, your HMI needs to have its own credentials if it connects as a device.

Each device, the router, and the HMI, create a separate secure connection.

So it seems you need to create a second device registration because of the 'Device ID' you mention:

-Hub Name -Device ID -SAS Token -CA certificate -TLS Version (I normaly use tls v1.0)

Still, it's not clear to me how this can work...

Devices do not share data between them directly. You need to add cloud-side logic (like an Azure Function) to route messages from one device to another:

industrial router -> Azure IoT Hub <-> Azure Function HMI <->

If a message is received from the router, it is sent to the Azure Function. There, logic can send it to other devices like the HMI.

Which HMI are you using? Are you following some manual?
Konstantinos Krikelis 0 Reputation points

2023-05-23T08:58:59.0066667+00:00

https://doc.exorint.net/jmobile/v4.05/en/Content/Manual/MQTT%20Client.htm

The MQTT interface is in its earliest stage in this HMI brand. I attached the only manual I've got and also what my configuration is.

Also can you maybe give me a reference or an example of how should I configure the logic to send the data to the HMI?

Thanks again, I really appreciate your help.
Konstantinos Krikelis 0 Reputation points

2023-05-23T09:11:54.9066667+00:00

The model name is exor ex710.
Sander van de Velde | MVP 36,761 Reputation points MVP Volunteer Moderator

2023-05-23T10:37:11.49+00:00

Hello @Konstantinos Krikelis,

the HMI seems to be capable to connect to Azure:

It's too specific to figure out how it works.

Please contact the manufacturer for more details regarding connecting it.

As an alternative for communication between the router and HMI over MQTT, please check out this upcoming presentation. Then you probably do not need to add extra server-side logic.

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Send data from iot device to HMI through azure iot hub using mqtt protocol.

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