Sending MQTT data to a HiveMQ broker using transmission module alone

Ignition
1

Hello Everyone,

I am looking to send OPC-UA data to a MQTT broker, I want to use HiveMQ, could this work by only using the cirrus Transmission module on ignition? or di I need to use an additional module?

Thanks in advance.

2

I think just the OPC UA and MQTT Transmission module would be enough.

Be aware that you're locked into the data being transmitted to HiveMQ in Sparkplug format.

3

Is there a way to transform it in another format using an additional module?

4

Not really.

The MQTT Engine module does provide a scripting function to publish an arbitrary message to an arbitrary topic, but at that point you're basically just rolling your own bridge using tag change scripts on OPC tags or something...

1 Like
5

The same script function exists on the transmission module so you can publish vanilla mqtt to your connected broker with just the transmission module.

Transmission Python Scripting

I have found though, that transmission seems to disconnect after each publish then reconnect again when you make your next call to that function. Perhaps if the connection was a websocket it might help, I haven't tested it.
I had a lot better performance and avoided this issue by calling the same function on the engine module instead. It used the same connection to the broker it created to subscribe to the configured topics at startup.